There are 140 balls in a box. 0.5 of them are red balls, and the rest are grey and brown balls. If there are 14 as many grey balls as brown balls. How many brown balls are there?
| Red balls |
Grey balls |
Brown balls |
Total |
| 1 u |
1 u |
2 u |
| |
1 p |
4 p |
|
0.5 =
510 =
12 Fraction of balls that are grey and brown balls
= 1 -
12 =
12 Total number of balls = 2 u
2 u = 140
1 u = 140 ÷ 2 = 70
Number of grey balls and brown balls
= 1 u
= 1 x 70
= 70
Number of grey and brown balls
= 1 p + 4 p
= 5 p
5 p = 70
1 p = 70 ÷ 5 = 14
Number of brown balls
= 4 p
= 4 x 14
= 56
Answer(s): 56
