Question

: The approximate value of \[1088.88 + 1800.08 + 1880.80\] equals
a.3950
b.4770
c.4620
d.5040

Answer 1

Hint: We are given three decimal numbers and to approximate its sum . First we need to add the numbers and round off the obtained sum

Complete step-by-step answer:
We are asked to find the approximate value of the sum \[1088.88 + 1800.08 + 1880.80\]
At first let's add the numbers and then approximate the value
Now adding the first two numbers we get
\[ \Rightarrow 1088.88 + 1800.08 = 2888.96\]
Now let's add the next number to the sum obtained
\[ \Rightarrow 2888.96 + 1880.80 = 4769.76\]
Now to obtain the approximate value the number after the decimal point 7 is greater than 5
Therefore the approximate value of the sum is 4770
The correct option is b.

Note: Rounding decimals refer to the rounding of decimal numbers to a certain degree of accuracy. We can round decimals to the nearest wholes, tenths or hundredths. Rounding decimals is useful to estimate an answer easily and quickly.
The precision of an approximate number is given by the position of the rightmost significant digit. Examples: The approximate number 8.617 has 4 significant digits. The digit 8 is the most significant digit and the digit 7 is the least significant digit.