Mathematics

1. In the equation AB+AC=BB,each letter represents an integer from 0 to 4.Different letters represent different integers.Suggest one valuefor each letter which satisfies the equation.

AB+AC=BB

Change into :

20A + B + C = 11B

20A + C = 10B

That C = 0

A = 1 , B = 2 OR , A = 2 , B = 4

2. Complete the following equation using directed numbers.
(-?+4)-(?+6)=10
?= ?=

( -A +4 ) - (A+6 ) = 10

4 - A - A - 6 = 10

- 2A - 2 = 10

- 2A = 12

A = -6

3.
Ricky's score
Round 1 : +12
Round 2 : +5
Round 3 : -18
Round 4 : +4
Daisy's score
Round 1 : -3
Round 2 : -7
Round 3 : +5
Round 4 : ?
The player getting a higher total score wins the game.If Daisy wins the game ,find the possible score
she got in the 4th round.

Ricky : 12 + 5 + 4 - 18 = 3

Daisy : 5 - 3 - 7 = - 5

she got in the 4th round : 3 - ( -5 ) = 8 or more

4. The prices of each pencil and each ruler are $4 and $3 respectively in a stationery store.Suggest how
Mable can use exactly $50 to buy some pencils and rulers.

5 pencil and 10 ruler

5. A hawer bought y oranges.Then he threw away 8 rotten oranges. He sold the remaining oranges at
$5 each.Ifhis total income was between $160 and$200,find two possible values of y.

5 ( y - 8 ) = 160

y = 40

5 ( y - 8 ) = 200

y = 48

y = 40 or 41 or 42 or 43 or 44 or 45 or 46 or 47 or 48

6. If 9 is 3 more than twice a number be x.
Let the number be x
9=?+?

9 = 3 + 2x

6 = 2x

3 = x

x = 3

7. John spends one-third of his money to buy a toy.Then he spends $20 for food.If he spends $37 in total,
how much money does he have at the beginning?
Let the money he has at the beginning be $x.

20 + x 1 / 3 = 37

x / 3 = 17

x = 51

8. A wire of 72cm long is bent into a rectangle.If the length of the rectangle is 19cm, find the width of the
rectangle.
Let the width of the rectanglebe y cm.

2y = 72 - 19 * 2

2y = 72 - 38

2y = 34

y = 17

9. In a school ,50% of the girls wear glasses while 280 of boys wear glasses.If the number of girls
wearing glasses is 2/7 of the number of boys, find the number of girls.
Let the number of girls be Y

2 / 7 * 280 * 2 = y

7 = 160