Question

On a team, 7 girls and 6 boys scored a total of 105 points. The difference between the number of points scored by the 7 girls and the number of points scored by the 6 boys is 21. Each girl scored the same number of points and each boy scored the same number of points. (Needs 2 equations) (Write the system)

Answer 1

Each girl scored 9 points

Each boy scored 7 points

Explanation:

Let the number of points each girl scored = a

Let the number of points each boy scored = b

7 girls and 6 boys scored a total of 105 points.

7a + 6b = 105......... Equation 1

The difference between the number of points scored by the 7 girls and the number of points scored by the 6 boys is 21

7a - 6b = 21........... Equation 2

7a + 6b = 105......... Equation 1

7a - 6b = 21........... Equation 2

Subtract Equation 2 from Equation 1

12b = 84

b = 84/12

b = 7

Therefore, each boy scored 7 points

7a + 6b = 105......... Equation 1

b = 7

7a+ 6b = 105

7a + 6(7) = 105

7a + 42 = 105

7a = 105 - 42

7a = 63

a = 63/7

a = 9

Therefore, each girl scored 9 points.