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Alexeev081 [22]
3 years ago
6

During one term Rachel took 2 mathematics test her mean score was 75 she scored 12 points more on the first test then the second

test how many points did she score on the second test
Mathematics
1 answer:
MaRussiya [10]3 years ago
3 0

Answer: she scored 69 points on the second test.

Step-by-step explanation:

Let x represent the number of points that she scored in the first test.

Let y represent the number of points that she scored in the second test.

If her mean score was 75, it means that

(x + y)/2 = 75

x + y = 75 × 2

x + y = 150- - - - - - - - - 1

If she scored 12 points more on the first test than the second test, it means that

x = y + 12

Substituting x = y + 12 into equation 1, it becomes

y + 12 + y = 150

2y + 12 = 150

2y = 150 - 12

2y = 138

y = 138/2

y = 69

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