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2 votes
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 cents 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?

User Rihards
by
6.0k points

2 Answers

2 votes

Answer:

20 six cent

30 eight stamp

10 ten cent

2 twenty centep explanation:

User Sarema
by
7.1k points
6 votes
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
User Yildizabdullah
by
7.3k points
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