3 years ago

The cost of 5 books and 4 pens is 115. if the cost of 1 book is RS 15 ,find the cost of 7 pens

Mathematics

1 answer:

Fynjy0 [20]3 years ago

7 0

Answer:

The cost of 7 pens is RS 70

Step-by-step explanation:

Let c=the cost of one book and p=the cost of one pen

5b+4p=115

b=15

5(15)+4p=115

75+4p=115

4p=115-75

4p=40

p=40/4

p=10

7p=7*10

7p=70

The cost of 7 pens is RS 70

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3 years ago

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