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Gwar [14]
3 years ago
7

The cost of a pen is 3 times the cost of a pencil and cost of a

Mathematics
1 answer:
valentinak56 [21]3 years ago
6 0

Answer:

1 Pen cost $2.25

Step-by-step explanation:

Assume:

Cost of Pen = a

Cost of pencil = b

Cost of notebook = c

a = 3b   -------------------(1)

c = 4a   -------------------(2)

2a + 6b + c = $18 -----(3)

From equation (1), b = a ÷ 3 ---------(4)

Substitute equations (2) and (4) in equation (3)

2a + 6 * (a ÷ 3) + 4a = $18

2a + 2a + 4a = $18

8a = $18

a = $2.25

Therefore, 1 Pen cost $2.25

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Answer:

Y = 5

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Step-by-step explanation:

I just solved it by my mind you just check it

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From the question we are told that

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