Prime numbers are numbers that have only one factor pair; 1 and themselves.
Let's start from 21.
21 = 1 x 21, 3 x 7.
This has two factor pairs, this is not prime.
Let's try 22.
22 = 1 x 22, 2 x 11.
This also has two factor pairs, this is not prime.
Let's try 23.
1 x 23.
This is a prime number, as it only has one factor pair; 1 and itself.
23 is your prime number.
I hope this helps!
To find the volume multiply all 3 numbers together.
2 1/2 x 1 1/2 = 3 3/4
3 3/4 x 3 = 11 1/4
The volume is 11 and 1/4 cubic units
Answer:
If the second person's pay is 891, then the 5th should be 1002.
Answer:
16
Step-by-step explanation:
4:2
2x4 = 8
4x4=16
The total number of fish bought was 320. And you know she bought two types of fish. The best way to solve this is guess and check. It would be the fastest. So she bought 7 times as many trigger-fish as parrot fish that means the number of trigger-fish bought was 7p. This means 320 = 7p +p. So all you do is take educated guesses for the number of parrot fish and check if it is right. So if she bought 50 parrot fish. 7(50) + 50 = 400. Close but a bit high. Lets keep guessing. 7(35) + 35 = 245. So now we know the answer is between 50 and 35. So lets try 40. 7(40) + 40 =320. That works so we know she bought 40 parrot fish and 280 trigger-fish.