Give the step-by-step reasoning process and then the final answer. Mike is building a bridge out of LEGO blocks. To be successful he needs at least 40 bricks of type A, and half that many of type B. In total, he needs to use 150 bricks. How many bricks of other types than mentioned is he going to use?
Mike is using 40 blocks / 2 = 20 blocks of type B. He uses in total 40 blocks + 20 blocks = 60 blocks of type A and B. So he is going to use 150 blocks - 60 blocks = 90 blocks of other types.
The final answer: 90.