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Vaselesa [24]
3 years ago
14

joanna went school supply shopping she spent $35.98 on notebooks and pencils notebooks cost $2.30 each and pencils cost $1.42 ea

ch she bought a total of 21 notebooks and pencils how many of each did she buy
Mathematics
1 answer:
Mumz [18]3 years ago
6 0

Joanna bought 7 notebooks and 14 pencils

Step-by-step explanation:

Step 1 :

Let x denote the number of notebooks and y denote the number of pencils Joanna bought.

Cost of one notebook = $ 2.30

Cost of one pencil = $1.42

Step 2 :

Total of notebooks and pencils bought  = 21

=> x + y = 21 => y = 21-x

Total cost of notebooks and pencils = $35.98

=> 2.3x + 1.42y = 35.98

Substituting y = 21- x here , we have,

2.3x + 1.42 ( 21-x) = 35.98

2.3x + 29.82 - 1.42x = 35.98

0.88 x = 6.16

=> x = 7

y = 21-x = 21-7 = 14

Step 3 :

Answer :

Joanna bought 7 notebooks and 14 pencils

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