Question

a prime number is a whole number that has exactly two different factors—1 and the number itself. a composite number is a whole number that has more than two different factors.
for each number:

• list all of its factors.
• write whether the number is prime or composite.
• circle all of the factors that are prime numbers.

number factors prime or composite?
① 11
② 19
③ 24
④ 29
⑤ 36
⑥ 49
⑦ 50
⑧ 70
⑨ 100

practice
solve.
⑩ 841 + 527 =
⑪ = 3,263 + 5,059
⑫ 7,461 + 2,398 =
⑬ = 4,172 - 3,236
⑭ 8,158 = 5,071 +
⑮ 3,742 - 3,349 =

Explanation:

Step1: Find factors of 11

The factors of 11 are 1 and 11 since \(1\times11 = 11\).

Step2: Determine prime - composite nature

Since 11 has exactly two factors (1 and 11), it is prime. The prime - factor is 11.

Step3: Find factors of 19

The factors of 19 are 1 and 19 since \(1\times19=19\).

Step4: Determine prime - composite nature

Since 19 has exactly two factors (1 and 19), it is prime. The prime - factor is 19.

Step5: Find factors of 24

The factors of 24 are 1, 2, 3, 4, 6, 8, 12, 24 because \(1\times24 = 24\), \(2\times12 = 24\), \(3\times8 = 24\), \(4\times6 = 24\).

Step6: Determine prime - composite nature

Since 24 has more than two factors, it is composite. The prime - factors are 2, 3.

Step7: Find factors of 29

The factors of 29 are 1 and 29 since \(1\times29 = 29\).

Step8: Determine prime - composite nature

Since 29 has exactly two factors (1 and 29), it is prime. The prime - factor is 29.

Step9: Find factors of 36

The factors of 36 are 1, 2, 3, 4, 6, 9, 12, 18, 36 because \(1\times36 = 36\), \(2\times18 = 36\), \(3\times12 = 36\), \(4\times9 = 36\), \(6\times6 = 36\).

Step10: Determine prime - composite nature

Since 36 has more than two factors, it is composite. The prime - factors are 2, 3.

Step11: Find factors of 49

The factors of 49 are 1, 7, 49 since \(1\times49 = 49\), \(7\times7 = 49\).

Step12: Determine prime - composite nature

Since 49 has more than two factors, it is composite. The prime - factor is 7.

Step13: Find factors of 50

The factors of 50 are 1, 2, 5, 10, 25, 50 because \(1\times50 = 50\), \(2\times25 = 50\), \(5\times10 = 50\).

Step14: Determine prime - composite nature

Since 50 has more than two factors, it is composite. The prime - factors are 2, 5.

Step15: Find factors of 70

The factors of 70 are 1, 2, 5, 7, 10, 14, 35, 70 because \(1\times70 = 70\), \(2\times35 = 70\), \(5\times14 = 70\), \(7\times10 = 70\).

Step16: Determine prime - composite nature

Since 70 has more than two factors, it is composite. The prime - factors are 2, 5, 7.

Step17: Find factors of 100

The factors of 100 are 1, 2, 4, 5, 10, 20, 25, 50, 100 because \(1\times100 = 100\), \(2\times50 = 100\), \(4\times25 = 100\), \(5\times20 = 100\), \(10\times10 = 100\).

Step18: Determine prime - composite nature

Since 100 has more than two factors, it is composite. The prime - factors are 2, 5.

Step19: Solve addition problem (10)

\(841+527 = 1368\).

Step20: Solve addition problem (11)

\(3263 + 5059=8322\).

Step21: Solve addition problem (12)

\(7461+2398 = 9859\).

Step22: Solve subtraction problem (13)

\(4172−3236 = 936\).

Step23: Solve addition - subtraction problem (14)

\(8158−5071 = 3087\).

Step24: Solve subtraction problem (15)

\(3742−3349 = 393\).

Answer:

Number	Factors	Prime or Composite?
19	1, 19	Prime
24	1, 2, 3, 4, 6, 8, 12, 24	Composite
29	1, 29	Prime
36	1, 2, 3, 4, 6, 9, 12, 18, 36	Composite
49	1, 7, 49	Composite
50	1, 2, 5, 10, 25, 50	Composite
70	1, 2, 5, 7, 10, 14, 35, 70	Composite
100	1, 2, 4, 5, 10, 20, 25, 50, 100	Composite
(10)	1368	-
(11)	8322	-
(12)	9859	-
(13)	936	-
(14)	3087	-
(15)	393	-