Estimated sum = 342
Actual sum = 342.23
Solution:
<u>Rule to rounding decimal number to whole:</u>
If the number after the decimal point is greater than or equal to 5, then add one number to the whole number and remove the decimal terms.
If the number after the decimal point is less than 5, then remove the decimal term and the whole number is as it is the same.
Nearest whole of 16.23 = 16 (decimal is less than 5, so as it is same whole)
Nearest whole of 215.7 = 216 (decimal is greater than 5, so add 1 number)
Nearest whole of 110.3 = 110 (decimal is less than 5, so as it is same whole)
Estimated sum = 16 + 216 + 110
Estimated sum = 342
Actual sum = 16.23 + 215.7 + 110.3
Actual sum = 342.23
Hence Len's estimated sum of the numbers is 342 and the actual sum of the numbers is 342.23.