Posted by **Joe** on Sunday, March 8, 2009 at 11:42am.

Sally took four tests in science class. On each successive test, her score improved by 3 points. If her mean score was 69.5%, what did she score on the first test?

- college algebra -
**Hannah Xx**, Sunday, March 8, 2009 at 11:47am
66.5%

- college algebra -
**Joe**, Sunday, March 8, 2009 at 12:08pm
thanks for the answer but can you please show how you got that answer

- college algebra -
**mark**, Sunday, March 8, 2009 at 12:36pm
the tests improve by 3 points, therefore:

test 1 x

test 2 x+3

test 3 x+6

test 4 x+9

the mean is the sum of the test scores divided by the number of tests. also, we know the mean = 69.5%

therefore, we get the equation:

(4x+18)/4 = 69.5%

4x+18 = 278

4x = 260

x = 65

therefore the score on the first test was 65%

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