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Lostsunrise [7]
3 years ago
9

Mario bought $5 worth of stamps at the post office. He bought ten more 6 cents stamps than 10 cents stamps. The number of 8 cent

s stamps was three times the number of 10 cents stamps. He also bought two 20 cents stamps. How many of each kind of stamp did he purchase?
Mathematics
2 answers:
vlabodo [156]3 years ago
6 0
S=number of 6 cent stamps
t=number of ten cen stamps
e=number of 8 cent stamps
w=number of 20 cents stamps=2

cost=500 cents
6s+10t+8e+20w=500
w=2 since two 20 cent stamps wer bought
6s+10t+8e+40=500
minsu 40 both sides
6s+10t+8e=460
divide both sides by 2 to simplify
3s+5t+4e+230


also
10 more 6 cent than 10 cent
s=10+t

8 cent stamps is 3 times 10 cent stamps
e=3t

sub
s=10+t
e=3t


3(10+t)+5t+4(3t)+230
30+3t+5t+12t=230
30+20t=230
minus 30
20t=200
divid 20
t=10

sub back
s=10+t
s=10+10
s=20

e=3t
e=3(10)
e=30





20 six cent
30 eight stamp
10 ten cent
2 twenty cent
Lerok [7]3 years ago
6 0

Answer:

20 six cent

30 eight stamp

10 ten cent

2 twenty centep explanation:

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<h3 />

<h3>How to solve variation ?</h3>

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