<span>To solve these GCF and LCM problems, factor the numbers you're working with into primes:
3780 = 2*2*3*3*3*5*7
180 = 2*2*3*3*5
</span><span>We know that the LCM of the two numbers, call them A and B, = 3780 and that A = 180. The greatest common factor of 180 and B = 18 so B has factors 2*3*3 in common with 180 but no other factors in common with 180. So, B has no more 2's and no 5's
</span><span>Now, LCM(180,B) = 3780. So, A or B must have each of the factors of 3780. B needs another factor of 3 and a factor of 7 since LCM(A,B) needs for either A or B to have a factor of 2*2, which A has, and a factor of 3*3*3, which B will have with another factor of 3, and a factor of 7, which B will have.
So, B = 2*3*3*3*7 = 378.</span>
Answer:
Step-by-step explanation:
Jack's method is equivalent because of the "law of commutative property", which means that multiplication problems have the same result no matter the order.
2x5 is the same as 5x2
Answer:
81583746
Step-by-step explanation:
It will be divisible by 6 if it ends in 6; when you divide you get 13,597,291.
Answer:
3 minutes per table
Step-by-step explanation:
15 minutes = 5 tables
to get how much it will be per table, divided both sides by 5
since 5 / x = 1 and x would be 5
15 / 5 minutes = 5 / 5 tables
3 minutes = 1 table
Answer: 9+4n-1 = 20
We can solve this by substitution.
Replace n with the value given, 3 (remember 4n means 4 times n):
9 + 4*3 - 1
Then work it out using arithmetic
9+12-1
=20
