Posted by Evelyn on .
Andy had 20% fewer marbles than Henry. When Andy gave 80 marbles to Henry, the numbers of marbles he had left was half of what Henry had. How many marbles did Andy have in the begining?
Please help me

math 
Reiny,
at start:
Henry  x marbles
Andy  .8x marbles
after giveaway:
Henry  x+80
Andy  .8x  80
Andy's marbles = 1/2 of Henry's marbles
.8x80 = (1/2)(x+80)
times 2
1.6x  160 = x+80
.6x = 240
x = 400
So Henry had 400 and Andy had 320
check: after giveaway
Andy is left with 240
Henry now has 480
Does Andy have half of what Henry has?? YES 
math 
Ariana Grande,
at start:
Henry  x marbles
Andy  .8x marbles
after giveaway:
Henry  x+80
Andy  .8x  80
Andy's marbles = 1/2 of Henry's marbles
.8x80 = (1/2)(x+80)
times 2
1.6x  160 = x+80
.6x = 240
x = 400
So Henry had 400 and Andy had 320
check: after giveaway
Andy is left with 240
Henry now has 480
Does Andy have half of what Henry has?? YES 
math 
sseexx,
400for henry 320 for andy