Estimating fractions

This task is about estimating a sum of fractions.
These questions are about estimating not solving to find the exact answer. For the each of the following three problems:
- Estimate what you think the sum of all the fractions is; and
- Explain how you worked out the estimate.
a)
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8989 + 14151415 + 21616
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b)
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715715 + 11121112 + 19181918 + 3
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c)
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23434 + 1212 + 25858 + 311311
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