Question

Ursula wrote the sum 5.815+6.021 as a sum of two mixed numbers.

a.What sum did she write? _____

b. Compare the sum of the mixed numbers to the sum of the decimals.______________

Answer 1

As the sum of mixed numbers:
5.815 = 5 + 815/1000
6.021 = 6 + 21/100
Therefore
5.815 + 6.021 = 5 + 6 + (815+21)/1000
= 11 + 836/1000
= 11 + 209/250

Part a.
The sum is
`11\, (209)/(250)`

Part b.
As the sum of decimals:
5.815
+ 6.021
----------
= 11.836

To compare the two results, evaluate209/250 as a decimal to see whether it is 0.836.

0.836
------------------
250 | 209.000
2000
--------
900
750
----------
1500
1500

Because 209/250 = 0.836, the two sums agree.