The product of two numbers is greater than 70 but less than 75. The sum of the two numbers is a multiple of 3. The difference between the two numbers is 21.
- Find the two numbers. Give your answers in the following format. (Eg 1, 2)
- Find the product of the two numbers.
(a)
Number greater than 70 and less than 74: 71, 72, 73 and 74
List the factors of 71, 72, 73 and 74.
71 = 1 x 71
72 = 1 x 72
72 = 2 x 36
72 = 3 x 2472 = 4 x 18
72 = 6 x 12
72 = 8 x 9
73 = 1 x 73
74 = 1 x 74
74 = 2 x 37
| |
Sum |
Multiple of 3 |
Difference |
Difference is 21 |
| 71 = 1 x 71 |
1 + 71 = 72 |
Yes |
71 - 1 = 70 |
No |
| 72 = 3 x 24 |
3 + 24 = 27 |
Yes |
24 - 3 = 21 |
Yes |
| 72 = 6 x 12 |
6 + 12 = 18 |
Yes |
12 - 6 = 6 |
No |
| 74 = 1 x 74 |
1 + 74 = 75 |
Yes |
74 - 1 = 73 |
No |
| 74 = 2 x 37 |
2 + 37 = 39 |
Yes |
37 - 2 = 35 |
No |
Two numbers: 3, 24
(b)
Product of the two numbers: 72
Answer(s): (a) 3, 24; (b) 72
