Answer: 4.9
Explanation:
You can use a calculator but I'll show you the step by step.
First,
is a mixed number. To be able to divide it, convert it to an improper fraction. You can do this by multiplying the big number by the denominator and adding the numerator; all of this over the same denominator.

Now, divide:
49/10=4.9
40
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9'0
90
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