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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89 + 1415 + 216
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b)
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715 + 1112 + 1918 + 3
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c)
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234 + 12 + 258 + 311
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