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.
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
__
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
