ShmoopTube
Where Monty Python meets your 10th grade teacher.
Search Thousands of Shmoop Videos
Pre-Algebra Videos 36 videos
ACT Math: Elementary Algebra Drill 5, Problem 4. How old is Thalia?
ACT Math: Pre-Algebra Drill 1.2. What proportion of Jenna's day is spent Wii-swimming?
ACT Math 3.1 Pre-Algebra 297 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.