Solution: Let Xiaohua have one yuan, then Xiaoming has a +85 yuan.
According to the meaning of the question
(a-30)×2=a+85-30
2a-60=a+55
A= 1 15 yuan.
Xiao Mingyou 1 15+85=200 yuan.
12. There is a rectangle. If its length and width are increased by 8 cm, its area will increase by 208 cm 2. It is known that the length of the original rectangle is 6 cm longer than the width. What is the area of the original rectangle?
Solution: if the width is a, then the length is a+6 cm.
Just draw it and you will know.
8a+8*(a+6)+8*8=208
8a+8a+ 1 12=208
16a=96
A=6 cm
Length = 6+6 =12cm
Area = 12×6=72 cm2.
13, A and B *** 140 yuan, A bought a book and used up 4/7 of his money. At this time, the money left by the two is the same. How much did Party A and Party B originally have?
Solution: Take the amount of armor as the unit 1.
Then the money brought by B is 1×( 1-4/7)=3/7.
So a originally had140/(1+3/7) =140/(10/7) = 98 yuan.
B The original money was 140-98=42 yuan.