Suppose there are x chickens and y cages.
4y+ 1=x
5(y- 1)=x
Get x=25, y=6.
6. Make tin cans with tin foil. Each tinplate can be made into 25 boxes or 40 boxes. A box body and two box bottoms can be made into a set of cans. There are 36 iron sheets. How many pieces can I use to make the box and the bottom just match?
Analysis: Because there are always 36 iron boxes, x+y=36. Formula; The number of sheets made in the box+the number of sheets made at the bottom of the box = the total number of sheets made in cans * * * 36. The equation (1) is obtained. Because now a box body and two box bottoms are made into a set of cans, so; Number of boxes *2= number of box bottoms. This will make them equal. Equation (2)2* 16x=40y is obtained.
x+y=36 ( 1)
2*25x=40y (2)
36-y=x (3) from ( 1)
Substituting (3) into (2) to obtain;
50(36 years) = 40 years
y=20
Substitute y=20 into (1) to get x= 16.
So; x= 16
y=20
Answer: Use 16 sheets as the box and 20 sheets as the bottom.
Tin cans are made of tin, and each tin can be used as 16 box or 43 box bottom, and a box with two box bottoms can be used as a set of cans. There are currently 225 sheets of iron. How many pieces are used in the box and bottom to make a complete set of cans?
X is the box body and y is the bottom of the box.
x+y=225( 1)
2× 16x=43y (2)
225-y=x (3) from ( 1)
Substituting (3) into (2) to obtain;
32(225-y)=43y
7200-32y=43y
75y=7200
y=96
If y= 16 is substituted (1), then x=225-96= 129.
So; x= 129
y=96
Or set X box and 225-x box.
2× 16x=43×(225-x)
32x=9675-43x
75x=9675
x= 129
Answer: Use 129 sheets as the box body and 96 sheets as the bottom of the box.
7. Now the total age of parents is six times that of children; Two years ago, the sum of parents' age and children's age was 10 times of children's age; The combined age of parents is three times that of children. Q: * * * When will the baby be born?
Solution:
The sum of parents' ages is X, the sum of children's ages is Y, and there are n children.
X=6Y
(X-4)= 10(Y-n*2)
6Y-4= 10Y-20N
4Y=20N-4
Y=5N- 1
(X+ 12)=3(Y+n*6)
6Y+ 12=3Y+ 18N
3Y= 18N- 12
Y=6N-4
6N-4=5N- 1
N=3
I have three children.