There are 2 groups of operators in a factory. There are 4 more operators in the first group than the second group. Each operator in the first group makes 7 toys in a minute but each operator in the second group makes only 3 toys in a minute. Both groups make a total of 18960 toys in 2 hours.
- How many operators are there in the first group?
- How many operators are there in the second group?
|
First group |
Second group |
Number |
1 u + 4 |
1 u |
Value |
7 |
3 |
Total value |
7 u + 28 |
3 u |
Number of operators in first group = 1 u + 4
Number of operators in second group = 1 u
Total number of toys made
= 7 u + 28 + 3 u
= 10 u + 28
1 h = 60 min
2 h = 2 x 60 = 120 min
Total number of toys made in 1 min
= 18960 ÷ 120
= 158
10 u + 28 = 158
10 u = 158 - 28
10 u = 130
1 u = 130 ÷ 10 = 13
Number of operators in the first group
= 1 u + 4
= 13 + 4
= 17
(b)
Number of operators in the second group
= 1 u
= 13
Answer(s): (a) 17; (b) 13