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 Question from Usama, a student: Convert the numbers used in the following expressions into those of base-five and solve : 21+34-108+62 Convert the result so obtained into decimal system and thus check your answer?

Hi Usama,

I can help get you started by converting 108 to base 5.

108 divided by 5 is 21 with a remainder of 3 so $108 = 21 \times 5 + 3.$ Next 21 divided by 5 is 4 with a remainder of 1. Hence

$108 = 21 \times 5 + 3 = (4 \times 5 + 1) \times 5 + 3 = 4 \times 5^2 + 1 \times 5 + 3 = 413_5$

Try to complete the problem now and write back if you need more assistance,
Penny

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