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Question 356709: Lani has a certain number of dollar bills in her purse. She has no other money. Lani spends half the money on a blouse and gives a dollar to a beggar outside the store. She spends half the remaining dollars for lunch and tips the waiter $2. She spends half the remaining dollars for a book, then goes to an ice cream parlor and spends $3 on a banana split. Lani now has one dollar bill left. Assuming that she never changed a dollar bill, how many bills did Lani start with?
Answer by mananth(16946)   (Show Source):
You can put this solution on YOUR website! Lani has a certain number of dollar bills in her purse. She has no other money. Lani spends half the money on a blouse and gives a dollar to a beggar outside the store. She spends half the remaining dollars for lunch and tips the waiter $2. She spends half the remaining dollars for a book, then goes to an ice cream parlor and spends $3 on a banana split. Lani now has one dollar bill left. Assuming that she never changed a dollar bill, how many bills did Lani start
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let her have $ x
x/2 for blouse
balance x/2
-1 beggar
x/2 -1
=(x-2)/2
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1/2 * (x-2)/2 for lunch
=(x-2)/4 for lunch.
-2 waiter
(x-2)/4 -2
=(x-2-8)/4
=(x-10)/4
1/2 (x-10)/4 for book
(x-10)/8 -3
x-10-24 /8
x-34/8 =1
x-34=8
x=42 dollars
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42 /2 = (blouse)21 -(beggar)1=20
1/2 *20= (lunch)10 -(tip)2=8
1/2 *8=(book)4 -(split)3= 1
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m.ananth@hotmail.ca
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