Janet lives in a city built on a grid system. She walks 3 blocks north, then seven times as many blocks west. Then she turns around and walks 8 blocks south and twice as many blocks east in the direction of her home. If Janet can walk 2 blocks/minute, how long will it take her to get home? Think carefully first, then make a decision:
First, find the total number of blocks south Janet is from her starting point by subtracting the blocks she walked north from the blocks she walked south: 8 blocks - 3 blocks = 5 blocks. Then find the number blocks she walked west: 3 blocks * 7 = 21 blocks. Then find the number of blocks she walked east: 8 blocks * 2 = 16 blocks. Subtract the number of blocks she walked east from the number of blocks she walked west to find how many blocks west of her starting point she is: 21 blocks - 16 blocks = 5 blocks. Add the number of blocks she needs to walk north to the number of blocks she needs to walk east: 5 blocks + 5 blocks = 10 blocks. Finally, divide the distance she needs to walk by her speed to find how long she'll spend walking: 10 blocks / 2 blocks / minute = 5 minutes. So, the answer is 5.