1968-11-26 — Page 15

25 NOV 1968

CITY HALL

真三策張四無

日七初月十年申伐歷夏

WAH KIU YAT PO #

二期星

日六廿月一十年八六九一整公年七十五國民中

温馨

1969 U13

數學科

牆四別之校

英

志羅

著榮生法斓學水,等運明

警胙校行

(四

飲陽絡文

明

LEG

頒

MATHEMATICS (4)

LESSON A: MISCELLANEOUS PROBLEUS I

The following are examples concerning with the preb-]

lens on clock and races, relative velocity, and

change of units etc.

EXAMPLE 1: In a mile bicycle race A boats B by 160 yd.

and beats C by 20 sec. If rides at 20 mph, find the speeds of A and B, be unifara.

SOL

C rides 20 min Inri

Crides 1 min se hr.

A rides at. in 3 min.-20 sec

•160 sec

's speed -

mi, per sec

日

文中學會考試題預習

assuming them ta

英文科

(四)

桂

in 160 sec. A. rides 1 mi.

in 160 sec, B. ridea i mi.-160 yd

EXAMPLE 2:

8's speed

To yd. per sec 10 yd. per sec.

17,60

*) 204 4. p.

16003

e.c. of a liquid, so. er. 0.65 are mixed with 12 c.c. of a llould, an, gr. 0.85, Find the ap. pr. of the mixtre, assuming there is no chemical reaction.

by definition, the specific gravity of a substance is defined as the ratio of the weight of any volu 4 or the substance to the weight of equal valame of pure water (at 4°c), which in a ratio

Bo.c. of the 1st liquid weigh 0.65x8 gm➡ 5:2gm 12c., of the 2nd liquid weigh 0.85 x 12gm 10.2ga 200.c. of the mixture weigh: 5.2gh+10, 2gúm: 15.4gm

**** 15.480 20 -0.77gm

EXAMPLE

Alt

I c.d of pure water weighs Lgn (at 4°C)` the sp. gr. of the dixture is 0.77 (0.77gm- Igm)

since

Atrain approaching a station at 60 m.p.h. blows a whistle every 5 sec. If sound travels at 1100ft per sec., find the intervals betw een the sound of thewhistles as heard by a mán on the station platform..

gec.

the train travels 60 mi 60 x 1760 × 3jft:

Cox176gr 3μ 5 It = 440rt

60 x 60

sound travels 1100 ft in

440 ft in

sec.

sec. 0,400

tho time-interval between the sounds heard

man on the platform is

5 sec. 0.4-.6 sec

ative Method: Solve by Algebra.

Suppose that the train is x away from the platform at the Ath Whistle.

440

speed of the train is 60 m.p.h.

sec., the train travels

the train is (X-440jft. away from the plate form at the (#1)th Whistle.

As given, sound travels at 1100ft. par Boc.

the difference between the whistles heard in the traini

(ENGLISH (4)

Answers to raper 111

naive: unaffected, simple, artless.

courting: trying to win affection or favour

3. enlisted enrolled for military service.

duration period.

prospect: expectation

b crotchety capricious, an constant

7. fanciful whimsical, incalculable

8. loathe: regard with disgust, de test,

9. vindictively revengefully

10. illusions: deceptions

1. (1) he had a thick head of nadr.

2. (ii) to read

3. (iii) the barber was glad to go to nussia with

armoured cars

(iii) he did not know what else to do

ii to gain freedom: for his son.

raper IV

orrect the following sentences:

The Mayor, as well as several, aldermen and counciliers, were present.

Everyone did what was rht in their own eye have any of these boys been here- cetcret Lou cannot mance me LC 40 it,

5. You need not too if you do not wish to.

of the two bonemes, this is the ne most likely to be adopted by the Government."

The evening ress" nas the largest carcuistion of any evening newspaper,

5. having arrived 100 inte for dinner, the in-

keeper refused to serve unem

You would be wise to carefully consider this matter before replying.

10. There have been less Labour disputes this year

than there were last year.

Punctuate the following passage:

maggie said mrs tolliver go and get your hair brushed do for shame to come out with the whispered, maggie pulling his sleeve as she passed him eno tom followed willingly enough. come upstairs with me tom She whispered krien they were outside the boor theres. something i want to go before dinner theres no time to play at anything before dinner said tom o yes there is time for his go come coin com followed maggie upstairs to her mothers room and saw her go: at once Lo a drawer from which she took out a large pair of scissors what are they for magie said tom feeling his curiosity awakened maggie answered ov seizing her front looks and cutting them straight across the middle of her forehead.

Complete the following proveros and explain them in your own words:

1. home was not built hy Keep & dog

Putting the cart...

Don't make mountains:

5. what can't be cured

6." You can't eat your cake

7 previty is the .......

•& Spare che rod and.

9. Turn over a new ...

100100, den det blood

Combine each set of sentences into a simple, Bentence.

ane completed his assignment, he went out for

walk. he wanted to refresh nimself.

2. The teacher sat down. His name was r Chan,

He began to address the class.

3. The bell has rung a long time ago. The pupils are expecting to see the te cher enter the at any moment.

The class was dismissed. The time was three o'clock. The teacher could now have is leisure The guests stood in two lines. The lines were arranged in opposite rows. The host gave out the

presents.

meeting had begun. The treasurer did not Turn up.

7. The old woman told the tragedy. Her fane was

covered with tears,

There was no more petrol in the car, it could not go on anymore,

The teacher advised the pupils. The teacher toi them that they should not spend extravagantly. Chirles Dickens way at first a court reporter, he wrote "Lavid Copperfield he desired to narrile aïs curly childhood.

Thousands of tourists locked to hongkong. They wtime from various parts of the world. They wanted to find on why Hongkong was called. "Ther Reard of the trient. V

12. The tech-r prohibited the pupils from opening),

thair Lext-books. It was his practice.

omplete the following expressions:

The Lirglar Uroke ・・・ jail and ran away.

hile everybody was asleep, the thief broke

The house and got away with the valuables hen, the Christmas season, arrives, the school breaks for the holidays. Toves heavy mike

she usually puts

As she

a lot of power and range on her face.

I do not know what care

to America.

him when he went

farseverance and pluck will carry a man

any difficulties.

The proposal he brought

оле

seeled a fooli

The king tried with all his efforts to bring

the peace;

There is a good deal of bad-feeling between the two men, can you do anything to bridge their differences?

10. The ping tried to bring

the rebels up. offering a free pardon to all who ould lay down their orma He showed violent oppos ṛtion at Kirsty but when the scheme was fully explained he came to our view,

12. the men of the village conferrea rogettiar

jainking a new well.s

the time-interval between

sounda heard at the

form:

Time taken for B to go round the track

mis. 480 sec:

kime taker for C to go round the tracki

· 200 sé

3002x 3 x 5.

480=2x 3x

800 2x 5:

(ANS, 6.02 2

The princ.

Time taken

The rate

தா.க.

5% per mth.

The amount at the end of 3 ath: 15.7625 115 15. 3d,

2105

Fi-Ist mt 11:5%

P2 2nd ath

5.25 12

10.25 P3;3rd ath

· 5.512513- 115.7629P4

EXAMPLE

·I c.c. of water weighs Iga; express the weight of i gall of water in lb., taking 1 cmm-0.393′ in., Icu. ft. 6.228 gall. I lbm0.4536kg.

M. of water weighs 1 gm

cu. in. of water weighs 0.001 kg..

Deel. kg.

4-

93937-70457b

16.228 gall

3937 HORN1b;

01927) 104536

(0-3737* X 64536

23957'

16.

EXAMPLE 5: Three man A,B,C go round a circular track 1

alle in circumference, in the same direction and starting together from the same place. A bicycles at 352 yd. per minute, Bruns at 220 vd per min., C walks at 132 vd. per min. After how many minutes will they first be Logether again at the starting-point?

SOL

The Dea if the circular track is 1 mix 1760 yd,

ime taken for A to go round the track is,

300 sec.,

3 x

the time they will first be together again at the starting-point is 12′x 3 x 5°) soc.

2*x3x5 min.se 40 min.

EXAMPLE 61A car travelling at 55 m.p.h. overtake at 3 pal

a'nan walking the same way at 4 mph, and met at 3:05 pm. Another man walking in the opposite direction at 43 mph. At what time will the two

den meet

In 5 min,, the 1st man walked at 4 max

car travelled 55 mix -472

3:05 pm, the distance between two pen is

any a pr...the distance covered by either:

14 + 42 J02 - 84 mi.

The two men can shorten the distance by 84 ml

les mt. in 30 min.

the time they meet is 3:05 pm + 30

the princ.

Then, $405.

HINTS & ANS, TO EX. 3.

320 and amount ➡ $40 $320 (1+ 4% 35

fọn t yr.)

1.042

405

320

3) For the Then

amount of 19500 at 4 49500 # P (T

19500

(ANS: paid * 1600 at once)

P be the original sum of money and Pamount] 2P in years at 5t p. Then, p 2P=&P ( !+5% )*

Let

to

21.05

ELERCISE &

!ANS::

Express a speed of 18 knota in mph, taking 1 Naut- icle mile as 6080 ft, and give the answer to 3 fig.!

21. If 150, 190 and 260 are each divided by a certain num- ber, the reminders are 3, 1, 8 resp., what is the greatest value of the divisor.”

Ec.c. of water at 4-C,weighs i gm, express the weight

of I gall of water in lb., given that I em, equals 0.3937 in.; I cu.ft. 6,228 gall., Elb-= ».4536kg

At what times do the hands of a clock contain an angle of 60 between 6 nm and 7 nm?

5) A train travelling at 31 mph passes a milestone.

at 2 pm; a train Y travelling the same way at 56mph passes this milestone at 2:25 pm. At what time will Yovertake. X 3.

Page 15Page 16

百四第四第

日七初月十年磨

WAH KIU YAT PO

B