Diana earned $150 in July. She earned 3 times this amount in August. In September, She earned twice the money she earned in August. How much money did Diana earn over these three months? Think carefully first, then make a decision:
The amount of money Diana earned in August is 3 * $150 = $450. The amount of money Diana earned in September is 2 * $450 = $900. The total amount of money Diana earned over the three months is $150 + $450 + $900 = $1500. So, the answer is 1500.