Question

Find prime factorizations of 3,210 and 3,528. Show your work.

Answer 1

Find the prime factorization of 3210
3210 = 2 × 3 × 5 × 107

Find the prime factorization of 3528
3528 = 2 × 2 × 2 × 3 × 3 × 7 × 7

To find the GCF, multiply all the prime factors common to both numbers:

Therefore, GCF = 2 × 3

GCF = 6


ANSWER: 6

Answer 2

9514 1404 393

Answer:

  3210 = 2·3·5·107

  3528 = 2³·3²·7²

Step-by-step explanation:

Divisibility rules help.

A number is divisible by 2 if it is even.

A number is divisible by 3 if the sum of digits is divisible by 3.

A number is divisible by 5 if it ends in 5 or 0.

A number is divisible by 7 if subtracting twice the 1s digit from the rest of the number results in a number divisible by 7.

3210

  Even, and ends in 0, so is divisible by 2·5

  3210/10 = 321

  Sum of digits is 6, so is divisible by 3

  321/3 = 107

  None of the divisibility rules applies, and √107 ≈ 10.3, so there are no prime factors of 107.

  3210 = 2·3·5·107

__

3528

  Ends in 2 digits divisible by 4, so is divisible by 4

  3528/4 = 882

  Even, so is divisible by 2

  882/2 = 441

  Sum of digits is 9, so is divisible by 9

  441/9 = 49

  This is recognizable as the square of 7.

  3528 = 2³·3²·7²