Question

A box contains orange balls and green balls. The number of green balls is ten more than three times the number of orange balls. If there are 98 balls altogether, then how many green balls and how many orange balls are there in the box?

Answer 1

Green balls = 76

Orange balls = 22

Explanation:

g = 10 + 3n Eq. 1

g + n = 98 Eq. 2

g = green balls

n = orange balls

From Eq. 2:

g = 98 - n Eq. 3

Equalizing Eq. 1 and Eq. 3

10 + 3n = 98 - n

3n + n = 98 - 10

4n = 88

n = 88/4

n = 22

From Eq. 3

g = 98 - 22

g = 76

Check:

from Eq. 1

g = 10 + 3n

76 = 10 + 3*22

76 = 10 + 66

Answer 2

76 green, 22 orange

Explanation:

`g + o = 98` g = green, o = orange, x = total

`g = 3o + 10`

use substitution: (3o + 7) + o = 67

solve for o:

`4o + 10 = 98`

`4o = 88`

`o = 88/4 = 22`

solve for g:

`g + 22 = 98`

`g = 76`