Question

Estimating $125\times 93$ to the nearest tens will give, while estimating to the nearest hundreds will give .

• A. $11,700$
• B. $10,000$
• C. $10,000$
• D. $15,000$

Answer 1

Answer: (A), (B)

$10,000$

For $125\times 93$, let's estimate it once to the nearest tens, while other to the nearest hundreds.
Now, for estimation to the nearest tens:
$125$ can be rounded off to $130$.
And, $93$ can be rounded off to $90$ as shown:

$\Rightarrow 125\times 93\approx 130\times 90$
And, $130\times 90=13\times 9\times 100$
$13\times 9$ can be calculated as:
$\Rightarrow 130\times 90=13\times 9\times 100=11,700$
$\Rightarrow 125\times 93\approx 11,700$

Now, for estimation near to hundreds:
$125$ can be estimated to $100$,
And, $93$ can be estimated to $100$ as shown:
$\Rightarrow 125\times 93\approx 10,000$

Now, let's calculate the exact product to compare:
So, $125\times 91$ can be simplified as:

Observation: $130\times 90=11,700$ is more clsoser to the real product i.e. $11,625$ than $100\times 100$.