Maths question
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Maths question
Please can someone help with this problem question
The money in Tim's wallet consists entirely of 2p and 5p coins. Sam asked him if he could change a £1 coin, but he was not able to do it exactly. What is the greatest amount of money that Tim could have in his wallet?
DD insists it is £1.04. Answer in booklet is £1.03.
DD's explanation:
99p is where she stopped using 2p and 5 p coins. But since the question asked for greatest amount, DD added another 5p coin to make £1.04.
DD said that this way, even though Tim has £1.04, he still cannot give Sam change of £1 exactly, but can only manage 99p, with the extra 5p coin hindering his (Tim's) objective of wanting to give Sam the exact change.
I am completely lost myself, as I had thought the answer was 99p.
The money in Tim's wallet consists entirely of 2p and 5p coins. Sam asked him if he could change a £1 coin, but he was not able to do it exactly. What is the greatest amount of money that Tim could have in his wallet?
DD insists it is £1.04. Answer in booklet is £1.03.
DD's explanation:
99p is where she stopped using 2p and 5 p coins. But since the question asked for greatest amount, DD added another 5p coin to make £1.04.
DD said that this way, even though Tim has £1.04, he still cannot give Sam change of £1 exactly, but can only manage 99p, with the extra 5p coin hindering his (Tim's) objective of wanting to give Sam the exact change.
I am completely lost myself, as I had thought the answer was 99p.
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Clearly 20 x 5p gives £1
But 19 x 5 gives a nice odd number... 95p
Bearing in mind 18 x 5 = 90p and we have 19 5ps so having 5x 2p would also bring us to £1; we must therefore have less than 5 2ps otherwise we would have reached £1 via the 18 x 5p route.
Therefore 19 x 5 + 4 x 2 is the max
i.e. £1.03
Tricky question
Regards
SVE
But 19 x 5 gives a nice odd number... 95p
Bearing in mind 18 x 5 = 90p and we have 19 5ps so having 5x 2p would also bring us to £1; we must therefore have less than 5 2ps otherwise we would have reached £1 via the 18 x 5p route.
Therefore 19 x 5 + 4 x 2 is the max
i.e. £1.03
Tricky question
Regards
SVE
Animis opibusque parati
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