Jenny washed dishes 4 times as many as her brother last month. her brother washed dishes 8 times. jenny said she could multiply 3 times 8 to find how many more times she washed dishes than brother. is jenny correct? explain.

Jenny is incorrect in her calculation.

For every time that Jenny's brother washed dishes, Jenny washed dishes 4 times. This tells that the the times they washed dishes occur in the ratio 4 :1. If Jenny's brother washed dishes 8 times, Jenny has to have washed dishes times. The way Jenny's is doing the calculation implies that his brother washed dishes times. He calculation yields a wrong result.

people went from manufacturing one object at a time by hand to manufacturing many objects in factories