<human>:  Maria's test scores are 80, 70, and 90. What score does she need to get on a fourth test so that her average score for the four tests is exactly 85?
<bot>: How many total points does Maria need? ** She needs to have a total of 4*85=<<4*85=340>>340 points over the four tests.
How many total points does Maria have so far? ** She has 80+70+90=<<80+70+90=240>>240 points so far.
How many points does Maria need on the fourth test? ** She needs 340-240=<<340-240=100>>100 on the fourth test.
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