Question 104887: Fifteen days after Alan began a diet he weighed 176 lb. After 45 days he weighed 170 lbs
a) how much did he weigh at the beginning of the diet?
b) At this rate, when will he weigh 165 lb?
Found 2 solutions by HyperBrain, edjones:
Answer by HyperBrain(694)   (Show Source):
You can put this solution on YOUR website! Let x=the rate that the diet eliminates the fat(weight)
y=his original weight
After 15 days, he has lost 15x lb
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After 45 days, he lost 45x lb
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If  and , then
This means that he loses 1/5 of a pound each day!!! What a diet!
But,
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And,
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Thus,
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He weighed a whopping 179 lb at the beginning!
NOw,let z=the no. of days required for him to be 165 pounds heavy.
After z days, he will lose x*z pounds.
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NOTE: I have subsituted x=1/5 and y= 179 already to avoid confusion about the three variables.
Continuing,
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He will wait for 70 days to be 165 lb!!!
Poer up,
HyperBrain!
Answer by edjones(8007)  (Show Source):
You can put this solution on YOUR website! He lost 6 of his 176 lbs in 45 days.
6/176=3/88
(3/88)(1/45)=1/1320 of his weight lost per day.
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let x be wt. before diet.
x-(15x/1320)=176
1305x/1320=176
x=176*1320/1305=178 lbs weight before diet.
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Let d=days it takes before he loses 11 more lbs.
176*d/1320=11
176d=11*1320=14520 multiply each side by 1320 to eliminate fraction.
d=14520/176=82.5 days
.
Ed
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