Question

1甲数的5.6倍与乙数的差,再乘3得63,已知乙数是7,求甲数.

Answer 1

1、设甲数为x,则(5.6x-7)*3=63 解得5.6x-7=21 5.6x=28 x=5

2、设该数为x,则x(7.1+8.7)=39.5 解得x=39.5/15.8=2.5

3、设甲数为x,则2.5x-2.7=2.9*2 解得2.5x=5.8+2.7=8.5 x=3.4

4、设该数为x,则x(2+13.7)=75.36 解得x=75.36/15.7=4.8