Adding
Subtracting
Multiplying
Dividing
Riddles
100

22/50 + 18/50

40/50

100

65/71 - 24/71

41/71

100

7/48 x 2/4

14/192

100

12/17 divided by 3/4

48/51

100

I add six to eleven and get five. This is true, but how is it possible?

It's possible on a clock.

200

33/100 + 58/100

91/100

200

85/95 - 29/95

56/95

200

32/45 x 8/9

256/405

200

53/60 divided by 7/9

477/420

200

Using only addition, combine eight 8's to make 1,000.

8 + 8 + 8 + 88 + 888 = 1,000

300

46/150 + 83/150

129/150

300

507/600 - 299/600

208/600

300

83/37 x 3/8

249/296

300

5/47 divided by 9/12

60/423

300

There is a three digit number. The second digit is four times bigger than the third. The first digit is three less than the second. What is it?

141

400

437/700 + 125/700

562/700

400

759/832 - 328/832

431/832

400

89/90 x 9/10

801/900

400

72/84 divided by 8/9

648/672
400

A father is four times older than his daughter. In 20 years time, she will be half as old as he is. How old are they now?

The father is 40 and the daughter is 10. 

500

507/1000 + 368/1000

875/1000

500

823/999 - 376/999

447/999

500

7/8 x 93/150

651/1200

500

87/99 divided by 9/10

870/891

500

Take two numbers, such that the square of the first plus the square of the second shall equal 8.

While the first plus the product of the first and the second shall equal 6. 

What are the two numbers?

2 and 2