the cost of a pencil is 25 cents more than the cost of an eraser. if the cost of 8 pencils and 10 eraser is $12.80, find the cost of each
Answers
Answered by
52
let the cost of each erasers be 'x ' and the cost of each pencils be 'y' .
First case:
----------------
cost of each pencils = 25 % more than the cost of eraser
cost of each pencils y = x + 25% of x
y = x + 0.25x = 1.25x
cost of each pencils y = $1.25x. -----(1)
second case:
--------------------
cost of 8 pencils and 10 erasers
= $12.80
8y + 10x = 12.80
8y + 10x = 12.80
8 ( 1.25x ) + 10x = 12.80
10x + 10x = 12.80
20x = 12.80 => x =$0.64
put value of 'x' in (1) , we get
y = 1.25x = 1.25 × 0.64
y = $0.80
Answer:
------------
cost of each pencils y = $0.80
cost of each erasers x = $0.64
First case:
----------------
cost of each pencils = 25 % more than the cost of eraser
cost of each pencils y = x + 25% of x
y = x + 0.25x = 1.25x
cost of each pencils y = $1.25x. -----(1)
second case:
--------------------
cost of 8 pencils and 10 erasers
= $12.80
8y + 10x = 12.80
8y + 10x = 12.80
8 ( 1.25x ) + 10x = 12.80
10x + 10x = 12.80
20x = 12.80 => x =$0.64
put value of 'x' in (1) , we get
y = 1.25x = 1.25 × 0.64
y = $0.80
Answer:
------------
cost of each pencils y = $0.80
cost of each erasers x = $0.64
ahilasreekrishna:
You wrongly understand the question. The question is 25 cent not 25 percentage
hehehehhe , whats you saying
Answered by
66
Pencil Eraser
25+x x
8(25+x)+10x=1280 [ 1 doller=100 cent
12.80 doller=1280 cent
200+8x+10x=1280
200+18x=1280
18x=1280-200
18x=1080
X=1080/18
X=60
Cost of a eraser= x = 60
Cost of a pencil= 25+x=85
total cost of 8 pencils and 10 erasers is $12.80 ....then how you can say that cost of 1 pencil = $80 , read question
60
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