Answer:
Step-by-step explanation:
Number of marbles with Betty = x
Number of marbles with Adelene = 3x
Adelene gives 25 marbles to Betty.
Now Adelene has (3x - 25) marbles and Betty has (x + 25) marbles.
3x - 25 = x + 25
Add 25 to both sides
3x - 25 +25 = x + 25 + 25
3x = x +50
Subtract x from both sides.
3x - x = x + 50 - x
2x = 50
Divide both sides by 2
2x/2 = 50/2
x = 25
Number of marbles with Betty = 25
Number of marbles with Adelene = 3*25 = 75
Marbles with both = 25 + 75 = 100
