ShmoopTube
Where Monty Python meets your 10th grade teacher.
Search Thousands of Shmoop Videos
Basics of Numbers Videos 8 videos
The precise placement of a decimal point can be the difference between life and death. Or... at least, between placing at the Olympics and falling...
If you plan on going from zero to hero, you'd better know your way around a number line. Oh wait... maybe that's just if you want to go from zero t...
Not just anyone can join the Integer Club. Watch this video to find out how you can make your way in.
SAT Math 4.3 Numbers and Operations 2174 Views
Share It!
Description:
SAT Math 4.3 Numbers and Operations
Transcript
- 00:02
Getting' Shmoopy with it...
- 00:04
If a and b are different prime numbers, which
- 00:06
of the following could also be prime?
- 00:08
And here are the potential answers...
- 00:13
The best way to deal with these questions
Full Transcript
- 00:15
is to substitute real prime numbers for the variables.
- 00:20
Let's say a = 2 and b = 3.
- 00:24
Now we can test each answer choice.
- 00:27
Choice A: 2 times 3 is 6. 6 is not prime. Boom -- gone.
- 00:32
Choice B: 2 cubed is 8. 8 isn't prime. Outta here.
- 00:37
Choice C: 2 plus 3 is 5. 5 is prime.
- 00:42
Choice D: 3 squared is 9. 9 isn't prime.
- 00:46
Only choice C can give us a prime number... ...so that's our answer.
- 00:57
An answer choice by any other letter would smell as sweet...
Related Videos
SAT Math 2.1 Geometry and Measurement. What is the measure of angle z in terms of x and y?
In 2014, the unemployment rate of one county in California was 7%. In another county, the unemployment rate was 11%. Which of the following express...
Angela is making cookies for a bake sale. She expects each batch of her cookies to sell for $40. It costs her $10 to make one batch of cookies, and...