Start by rounding 412 and finding 1 % of the rounded number.
About 2
Practice makes perfect
We want to estimate 12 % of 412. We will start by rounding 412.
rcl
412 & ≈ & 400
Now we can find 12 % of 400 to get an estimation. To do so, let's start by finding 1 % of 400 by multiplying these two quantities. Recall that 1 % is equal to 1100.
We found that 1 % of 400 is equal to 4. Now let's find 12 % of 400. We can do this using the fact that 12 % is 12 of 1 %.
rcr
1 %of 400 & = & 4 [0.3em] & ↓ & [0.3em]
12of 1 %of 400 & = & 12of4 [0.3em] & ↓ & [0.3em]
12 %of 400 & = & 12of4
Finally, let's calculate 12 of 4 by multiplying these two numbers. This will give is the desired estimation.
