Question. Brenda raises mice, and her adult mice recently had three litters of 8 each. She gave a sixth of the baby mice to her friend Robbie to keep as pets. She sold three times the number of babies she gave Robbie to a pet store. Half of the remaining mice were sold to snake owners as feeder mice. How many baby mice did Brenda have left?
Answer. 4
What step-by-step reasoning justifies that answer?
Reasoning: Brenda's mice had 3 * 8 = 24 baby mice. She gave Robbie 24 / 6 = 4 mice. Thus, she sold 3 * 4 = 12 mice to the pet store. She had 24 - 12 - 4 = 8 mice remaining. She sold 8 / 2 = 4 as feeder mice. Thus, Brenda had 8 - 4 = 4 mice left.