ShmoopTube
Where Monty Python meets your 10th grade teacher.
Search Thousands of Shmoop Videos
Fractions and Decimals Videos 17 videos
Worried about adding and subtracting fractions? Never fear. It's so easy that it will only take up a fraction of your time: just use multiplication...
ACT Math 3.1 Pre-Algebra 298 Views
Share It!
Description:
ACT Math: Pre-Algebra Drill 3, Problem 1. Calculate (0.3) 4 .
Transcript
- 00:03
Shmooper-califragilistic-mathialidocious...
- 00:07
Calculate: point-3 to the 4th power.
- 00:10
And here are the potential answers...
- 00:14
OK, so what's this exponent problem testing?
- 00:17
It's really all about the concept of multiplying numbers SMALLER than 1.
Full Transcript
- 00:21
If we think about it -- and yeah, it may hurt...
- 00:25
...1 times 1 times 1... is always gonna be 1. That's why it's the loneliest number.
- 00:31
And if we multiply a number a bit bigger than 1 again and again and again like an infinite
- 00:37
number of times, our result will... also be infinite.
- 00:41
But if a number is SMALLER than 1 and we multiply it a bunch of times, it'll get closer and
- 00:48
closer to... zero.
- 00:49
In this case, we are multiplying less than a third of 1... so at the end of the day it
- 00:55
should be a really small number because we are multiplying it 4 times.
- 01:00
Just understanding this concept generally, we can get rid of B and D immediately... and
- 01:05
A as well, really.
- 01:07
But if we just brute force the math, we get point 3 times point 3 which is point ZERO
- 01:13
9.
- 01:14
There were TWO units to the right of the decimal -- here and here...
- 01:17
...so we need two units to the right of the decimal in our answer.
- 01:21
Now we multiply by .3 again and we have .027 -- yeah -- THREE numbers to the right of
- 01:27
the decimal.
- 01:28
Do it one last time and we have .0081... FOUR units to the right of the decimal.
- 01:34
So the answer is E.
- 01:35
As in, "Everybody's busy."
Related Videos
ACT Math: Plane Geometry Drill 3, Problem 1. What is the area of the trapezoid shape in the video?
ACT Math: Coordinate Geometry Drill 1, Problem 1. Which inequality is expressed by the number line?
ACT Math: Intermediate Algebra: Drill 3, Problem 1. Find the fifth number in the series.