There are 280 balls in Diana's collection. The number of her black balls is 6 times the number of her grey balls.
- How many grey balls does she have?
- How many black balls does she have?
(a)
Number of grey balls = 1 u
Number of black balls = 6 u
Total number of balls
= 1 u + 6 u
= 7 u
7 u = 280
1 u = 280 ÷ 7 = 40
Number of grey balls
= 1 u
= 40
(b)
Number of black balls
= 6 u
= 6 x 40
= 240
Answer(s): (a) 40; (b) 240