Question

Ed buys a box of eggs costing £2.30, two packs of bacon for £2.60 each and two tins of baked beans.
He pays with a £10 note and gets 80p change.
How much does a tin of beans cost in pounds, £?

Answer 1

Answer:

1 tin of baked beans costs 85p, or £0.85.

Step-by-step explanation:

Cost of 1 box of eggs = £2.30

Cost of 1 pack of bacon = £2.60

∴ Cost of 2 packs of bacon = 2 × £2.60 = £5.20

We don't know the cost of 1 tin of baked beans, so let us set it as £X

∴ Cost of 2 tins of baked beans = 2 × £X = £2X

We know that, sum of the costs of all the items purchased by Ed equals to the amount he paid minus the change he received.

⇒ Cost of 1 box of eggs + Cost of 2 packs of bacon + Cost of 2 tins of baked beans = Amount Ed paid - Change Ed received

We know that.

Amount Ed Paid = £10.0

Change Ed received = £0.80

(100 pence equals 1 pound, thus 80 pence equals 0.8 pound)

Now, we can plug in the amounts into the equation to find the cost of 1 tin of baked beans since that is the only unknown value.

⇒ £2.30 + £5.20 + £2X = £10.0 - £0.80

⇒ £2.30 + £5.20 + £2X = £9.20

⇒ £7.50 + £2X = £9.20

On subtracting both sides by £7.50 we get,

⇒ £7.50 - £7.50 + £2X = £9.20 - £7.50

⇒ £2X = £9.20 - £7.50

⇒ £2X = £1.70

⇒ £X = £1.70/2

⇒ £X = £0.85

Therefore a tin of beans costs £0.85, or 85 pence.

Verification:

Now if we add up the costs of all the items purchased, we must get £9.20 if our answer is correct.

⇒ Cost of 1 box of eggs + Cost of 2 packs of bacon + Cost of 2 tins of baked beans

⇒ £2.30 + £5.20 + £2(0.85)

⇒ £2.30 + £5.20 + £1.70

⇒ £7.50 + £1.70

⇒ £9.20

This amount matches the amount Ed paid, thus the answer is correct.