Question

Greg and Cleo are playing a game and they each have a certain number of chips. Greg starts with twice as many chips as Cleo. After he gives her 8 chips, he still has 9 more than Cleo. How many chips did Greg have before he gave the 8 chips to Cleo?
A) 18
B) 34
C) 48
D) 50

The correct answer is D, but how do you get it?

Answer 1

Answer:

50

Step-by-step explanation:

I toke me a lot of time to figure out why am I getting always 34 and still it isn't working : 34-8 = 26 and 26-25=1 wich is false

now I'll show you how

• Let x be the number of chips that Greg has and y the number of chips that Cleo has
• Greg starts with twice as many chips as Cleo so we can say : x=2y
• so we can state : x-2y=0

Greg gives Cleo 8 chips but still he has 9 more chips than Cleo :

• so x-8 is the number of chips that Greg has
• the trick now is to notice that he gave those chips to Cleo , he didn't left them . so the number of chips that Cleo has is y+8
• we khow that now after giving the chips Greg has 9 more chips than Cleo so basically we can write :  x-8-(y+8) = 9  
• The equation will be : x-y=25

I guess now that we we are smelling that 50

• our two equations are : x-2y = 0 and x-y-25=0
• let's multiply x-2y by (-1) to get rid of x

we get -x+2y=0 and all we should do now is to add it to the second equation to make a normal one with one unkhown value y

• -x+2y+x-y-25=0 ⇒ y=25

• so x = 2*y=2*25=50

finaaly the aswer is 50

the trick is to try to imaginate the situation