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Phillip has twice as many tropical fish as Jody. If Phillip
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10 Mar 2019, 10:38
10 Mar 2019, 10:38
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Question Stats:
71% (01:38) correct
28% (01:57) wrong based on 28 sessions
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Phillip has twice as many tropical fish as Jody. If Phillip gave Jody 10 of his tropical fish, he would have half as many as Jody. How many tropical fish do Phillip and Jody have together?
A. 10
B. 20
C. 30
D. 40
E. 60
A. 10
B. 20
C. 30
D. 40
E. 60
examPAL Representative
Joined: 27 Nov 2018
Posts: 37
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Re: Phillip has twice as many tropical fish as Jody. If Phillip
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12 Mar 2019, 06:49
12 Mar 2019, 06:49
1
1) p = 2j
2) P-10 = (j+10)/2 --- we'll plug in (1):
2j-10=(j+10)/2 --- multiply by 2:
4j-20=j+10
3j=30
j=10
p=2*10=20
P+j=30
2) P-10 = (j+10)/2 --- we'll plug in (1):
2j-10=(j+10)/2 --- multiply by 2:
4j-20=j+10
3j=30
j=10
p=2*10=20
P+j=30
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Joined: 10 Apr 2015
Posts: 6218
Given Kudos: 136
Re: Phillip has twice as many tropical fish as Jody. If Phillip
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12 Mar 2019, 07:29
12 Mar 2019, 07:29
1
Carcass wrote:
Phillip has twice as many tropical fish as Jody. If Phillip gave Jody 10 of his tropical fish, he would have half as many as Jody. How many tropical fish do Phillip and Jody have together?
A. 10
B. 20
C. 30
D. 40
E. 60
A. 10
B. 20
C. 30
D. 40
E. 60
We can also solve this question using 1 variable
Phillip has twice as many tropical fish as Jody.
Let x = # of Jody's fish
So 2x = # of Phillip's fish
If Phillip gave Jody 10 of his tropical fish, he would have half as many as Jody
After Phillip gives Jody 10 fish....
Let x + 10 = NEW # of Jody's fish
So 2x - 10 = NEW # of Phillip's fish
We're told that: (number of Phillip's fish) = (1/2)(number of Jody's fish)
So, we can write: 2x - 10 = (1/2)(x + 10)
Expand to get: 2x - 10 = 0.5x + 5
Subtract 0.5x from both sides to get: 1.5x - 10 = 5
Add 10 to both sides: 1.5x = 15
Solve: x = 15/1.5 = 10
So, Jody has 10 fish (because x = 10)
Since 2x = Phillip's fish, then Phillip has 20 fish
How many tropical fish do Phillip and Jody have together?
TOTAL fish = 10 + 20 = 30
Answer: C
Cheers,
Brent
