Number theory 4B SW

Daniela's teacher asked the class to guess her age and gave them the following clue. She told them her age was a prime number between 50-60. Which of the numbers below could be the teacher's age?

Which picture shows a prime number of stars?

In which numeral is the digit in the ten millions place a prime number?

Marin's math assignment is to write factor pairs that contain only composite numbers. He wrote the four factors pairs for the number 136 as shown below.

A: 1 x 136

B: 2 x 68

C: 4 x 34

D: 8 x 17

Which of Marin's factor pairs contains only composite numbers?

The table shows the number of factors for different numbers.

Which of these numbers is a prime number?

Lily's teacher asked her to list all the factor pairs for 42. The factor pairs Lily wrote are shown below.

1 and 42

2 and 21

6 and 7

Her teacher told her that she is missing one factor pair. Choose the missing factor pair for 42.

This picture shows four balls drawn in a bingo game. Which ball does NOT have a prime number?

Is 2 a prime or composite number?

How many factors does the number 18 have?

Which statement about the number 17 is true?