Mathematics fifth grade score formula, application problems 1、 Use the recursive equation: 1. 5 / 8 - 1 / 3 + 2 / 9, 2. 3 / 20 - (7 / 8 - 17 / 20) 2、 Five out of seven known

Mathematics fifth grade score formula, application problems 1、 Use the recursive equation: 1. 5 / 8 - 1 / 3 + 2 / 9, 2. 3 / 20 - (7 / 8 - 17 / 20) 2、 Five out of seven known

1.5/8-1/3+2/9=7/24+2/9=37/72
3/20-(7/8-17/20)=3/20-7/8+17/20=1/8
2. A can be a number between 13
3. VA = 2 * 2 * 5 = 20 cubic decimeter
VB = 1 / 4va = 20 * 1 / 4 = 5 cubic decimeter
Because of the same level of water
So the bottom area of B = 5 / 5 = 1 square decimeter