<human>:  Brittany got a 78 on her first test. After her second test, her average rose to an 81. What grade did she get on her second test?
<bot>: How many points did Brittany score on her second test? ** First multiply her average grade by the number of tests she took to find the total number of points she scored: 81 points * 2 = <<81*2=162>>162 points
How many points did Brittany score on her second test? ** Then subtract the number of points she scored on her first exam to find how many points she scored on her second exam: 162 points - 78 points = <<162-78=84>>84 points
#### 84