22nD Feb

A small box can hold 10 balls.

Four medium boxes can hold the same number of balls as eight small boxes.

Three big boxes can hold the same number of balls as six medium boxes.

How many balls can 2 big boxes hold?

• 20

• 100

• 160

• 80 

• 40

Answer explanation

3 big boxes  = 6 medium boxes

               

1 big box  = 2 medium boxes.

               

2 medium boxes  = 1 big box

               

4 medium boxes  = 2 big boxes

               

8 small boxes = 2 big boxes

               

8 X 10 balls  = 2 big boxes

If 3 masons construct a wall in 10 days. 

In how many days 5 such masons can construct the wall?

• 10 days

• 5 days

• 9 days

• 6 days

• 8 days

Answer explanation

x/10  =  3/5

Masons and days are inversely proportional

By simplifying: 

x = 6 days

Sarah spent 480 dollars to purchase 5kg of apples and 2kg of mangoes. 

Find the price of 1kg of apples if the rate of apples is double the rate of mangoes.

• $80

• $60

• $70

• $40

• $90

Answer explanation

Let rate of 1kg mangoes = x

Then rate of 1kg apples = 2x

Total purchase = 5 × 2x + 2x 

= 480

12x = 480 

x = 40   

Rate of 1kg apples = 2x = 80

In a mineral water bottle factory, 6 identical machines can produce 900 bottles per minute. At this rate, how many bottles could 10 such machines produce in 5 minutes?

• 1500

• 108

• 5400

• 2700

• 7500

Answer explanation

Let the number of bottles be 𝑥.

Number of machines – 6: 10

Number of minutes– 1: 5

Number of bottles = 900: 𝑥

6*1/900 = 10*5/𝑥

𝑥 = 50 x 900/6

𝑥 = 7500

10 machines can produce 7500 bottles in 5 minutes

Tim and Vic had 5400 dollars.

Vic had five times as many as Tim had.

How much money did each of them have?

• Vic 4800

  Tim 600

• Vic 3800

  Tim 1600

• Vic 600

  Tim 4800

• Vic 5000

  Tim 400

• Vic 4200

  Tim 600

A tap can fill a tank in 5 minutes. If four such taps are turned on at the same time, how long will it take them to fill the tank?

• 2 minutes and 30 seconds

• 1 minute and 40 seconds.

• 1 minute and 20 seconds.

• 5 minutes

• 3 minutes and 20 seconds

Andrew bought an Ipad during the EOFYS sale and saved $441 from the recommended retail price. Amazon was selling all electronic products at a 25% discount. What is the recommended retail price and how much did Frederica pay for her new iPhone?

• 1764, 1323

• 1130, 1904

• 1030, 1256

• 1832, 1441

• 1640,1240

Three boys A, B and C have 225 cards.

To share cards equally, C gives 25 to B and B gives 15 to A.

Each now has the same number of cards.

What was the difference in the number of cards A and C have originally?

• 32

• 25

• 35

• 40

• 30

Answer explanation

All boxes finally have the same number of cards =  = 75 cards.

25 cards moved from C, so C - 25 = 75 or C = 100.

15 cards added to A to make it 75, so A + 15 = 75 or A = 60.

So the difference in the original number of cards of C and A = 100 - 60 = 40.

Serena has 500 cookies that she plans to sell between Monday and Friday. On Monday, she sells 60 cookies. On Tuesday, she sells twice as many cookies as she did on Monday. On Wednesday and Thursday, she sells the same number of cookies. On Friday she sells half as many cookies as she did on Thursday. How many cookies did Serena sell on Friday?

• 120

• 128

• 180

• 64

• 60

Answer explanation

Step 1:

As twice as many cookies were sold on Tuesday than on Monday, 2 x 60 = 120 cookies were sold on Tuesday.

 

Step 2:

Hence, 60 + 120 = 180 cookies were sold over both days, implying that 500 – 180 = 320 cookies were sold over Wednesday, Thursday, and Friday.

 

Step 3:

Let the number of cookies sold on Friday be c.

 

Step 4:

We know that the number of cookies sold on Thursday must therefore be 2c (half of 2c is c). Consequently, 2c cookies must have also been sold on Wednesday.

 

Step 5:

Thus, we have that the number of cookies sold over the last three days is 2c + 2c + c = 5c = 320.

 

Step 6:

As such, c = 320/5 = 64.

 

Thus, the answer is 64.

One-third of the chocolates in a carton was expired. Of the number left there was enough to give two chocolates to each of five children. 

How many chocolates were originally in the carton?

• 15

• 30

• 12

• 25

• 20