Question

Find in how many days the machine finished the boring process.

• A. 11
• B. 1,100
• C. 110
• D. 1.1

Answer 1

The correct option is C 110

Total amount of boring done by the machine = 23 km 100m
The machine bores 210 m daily.

∴ Number of days = Total amount of boring ÷ Boring done every day
$\text{⇒ Number of days}=23km100m÷210m$

Step 1: Convert the total amount of boring done to a common unit (m).

$\text{We know,}1km=1,000m$
$\Rightarrow 23\text{km}=1,000\times 23\text{m}$
$\Rightarrow 23\text{km}=23,000\text{m}$


So, total amount of boring = 23,000 km + 100 m = 23,100 m

Step 2: Divide the total amount by the amount bored every day using long division method.

$$\begin{array}{c}110\\ 21023100\\ -\underset{–}{210}2\\ 210\\ -\underset{–}{210}\\ 0\\ -\underset{–}{0}\\ 0\end{array}$$
So, the boring machine finished the process in 110 days.