This is the second of our medium level Eleven Plus maths quizzes on multiplication and division. In the first, we learned some handy techniques for multiplying and dividing which, if you remember them, will improve your mental arithmetic considerably. The best way to remember something of course, is to practice!

Here are some tips which may help you:

- To multiply by 11, first multiply by 10, then add the original number
- To multiply by 9, first multiply by 10, then subtract the original number
- To divide by 5, first multiply by 2 and then move the decimal point to the left
- To divide by 25, divide by 100, then multiply by 4

There are many more useful strategies you can use – you may even have some of your own. Whatever method you choose, as long as you reach the correct answer quickly, then it’s fine. Now try these teasers and see how you fare. Good luck!

1.

What is the correct answer to the given calculation?

627 × 25 = ?

627 × 25 = ?

15,675

15,765

15,576

15,756

2.

What is the correct answer to the given calculation?

326 ÷ 5 = ?

326 ÷ 5 = ?

0.652

652

6.52

65.2

To divide a number by 5: first multiply by 2 and then move the decimal point (d.p.) to the left:

326 ÷ 5 = (326 × 2) ÷ 10 = 652 ÷ 10 . Move the d.p. 1 place to the left gives 65.2

326 ÷ 5 = (326 × 2) ÷ 10 = 652 ÷ 10 . Move the d.p. 1 place to the left gives 65.2

3.

What is the correct answer to the given calculation?

27 × 101 = ?

27 × 101 = ?

27,270

272.7

2,727

2,277

To multiply a number by 101, first multiply by 100 then add the original number:

27 × 101 = (27 x 100) + 27 = 2,700 + 27 = 2,727

27 × 101 = (27 x 100) + 27 = 2,700 + 27 = 2,727

4.

What is the correct answer to the given calculation?

134 × 12 = ?

134 × 12 = ?

1,608

1,806

1,068

1,680

To multiply a number by 12, first multiply the number by 10, then add twice the original number to it:

134 × 12 = (134 x 10) + (134 x 2) = 1,340 + 268 = 1,608

134 × 12 = (134 x 10) + (134 x 2) = 1,340 + 268 = 1,608

5.

What is the correct answer to the given calculation?

714 × 11 = ?

714 × 11 = ?

7,548

7,485

7,854

7,845

To multiply a number by 11, first multiply the number by 10, then add the original number to it:

714 x 11 = (714 x 10) + 714 = 7,140 + 714 = 7,854

714 x 11 = (714 x 10) + 714 = 7,140 + 714 = 7,854

6.

What is the correct answer to the given calculation?

475 ÷ 25 = ?

475 ÷ 25 = ?

17

18

19

20

To divide a number by 25: divide by 100, then multiply by 4:

475 ÷ 25 = (475 ÷ 100) x 4 = 4.75 x 4 = 19

475 ÷ 25 = (475 ÷ 100) x 4 = 4.75 x 4 = 19

7.

What is the correct answer to the given calculation?

394,227 ÷ 1,000 = ?

394,227 ÷ 1,000 = ?

3.94227

394.227

3,942.27

39.4227

To divide a number by a multiple of 10 whose only non-zero digit is the leading digit 1: move the decimal point (d.p.) to the left by the same number of zeros that are in the multiple of 10, in this case 3 places as there are 3 zeros in 1,000

8.

What is the correct answer to the given calculation?

212 × 9 = ?

212 × 9 = ?

1,809

1,098

1,980

1,908

To multiply a number by 9: first multiply the number by 10, then subtract the original number from it:

212 × 9 = (212 x 10) - 212 = 2,120 - 212 = 1,908

212 × 9 = (212 x 10) - 212 = 2,120 - 212 = 1,908

9.

What is the correct answer to the given calculation?

96 × 80 = ?

96 × 80 = ?

7,608

7,860

7,086

7,680

To multiply a number by 80, multiply the number by 2, then by 2 again, and again by 2, and finally by 10:

96 × 80 = (96 x 2 x 2 x 2) x 10 = (192 x 2 x 2) x 10 = (384 x 2) x 10 = 768 x 10 = 7,680

96 × 80 = (96 x 2 x 2 x 2) x 10 = (192 x 2 x 2) x 10 = (384 x 2) x 10 = 768 x 10 = 7,680

10.

What is the correct answer to the given calculation?

2,343 × 5 = ?

2,343 × 5 = ?

11,157

11,715

11,571

11,175

To multiply a number by 5: first divide by 2, then move the decimal point (d.p.) to the right:

2,343 × 5 = (2,343 ÷ 2) x 10 = 1,171.5 x 10. Move the d.p. 1 place to the right gives 11,715

2,343 × 5 = (2,343 ÷ 2) x 10 = 1,171.5 x 10. Move the d.p. 1 place to the right gives 11,715

627 × 25 = (627 x 100) ÷ 4 = 62,700 ÷ 4 = 15,675