Question

10 pens cost £4.00 find the cost of 7 pens

Answer 1

Well, the first thing we need to do is divide 10 by 4. These teo numbers are the number of pens, and cost of them. So,
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10 / 4 = 2.5
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Now we have to use the answer we got, 2.5 which is the cost of 1 pen, and multiply it by 7.
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2.5 x 7 = 17.5
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This means that 7 pens cost £17.5

Answer 2

The answer is £2.80. To find the cost of 1 pen, you divide £4 (all 10 pens) by 10 which gives you 40p. To find 7 pens, you multiply 40p (1 pen) by 7. £0.40 x 7 = £2.80