Question

box a contains 225 ends. Box B contains 320 rulers. Some pens were moved from box to box B and some rulers were moved from box be to box a. In the end and 3/10 of the items in box a and 3/5 of the items in box B were pens. How many rulers were moved from box be to box a?​

Answer 1

Answer: 238 rulers

Step-by-step explanation:

Box A=225 pens and box B= 320 rulers

Things in box A=x and things in box B=y (because box A items are over 10 and items in box B are over 5)

Box A = 3/10 are pens (all items in this box are called x)

x + x + x = 3x

y +y+y+y+y+y+y = 7x (rulers moved from box B)

Box B = 3/5 pens

x + x + x = 3y (pens)

x + x = 2y (rulers)

System of equations:

3x + 3y = 225 and 7x + 2y = 320 (simplify the first equation, divide by 3 and multiply by -2 to cancel 2y)

(3x+3y=225)/3 = x+y=75

-2(x+y=75)= -2x-2y= -150

Add both equations

(-2x-2y= -150) + (7x+2y=320) =

5x = 170

X = 34

7*34=238