I have two dogs who eat the same dog food. I have ten tins of dog food. Gnasher eats a tin of food in two days; Nibbles eats a tin of food in five days. What is the latest day on which I must buy some more tins of dog food?
Select one option, then click Submit.
1st day
7th day
10th day
15th day
16th day
Select an option, then submit.
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Primary Mathematics Challenge 2005 (2005)
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