50. (Biggest # - smallest #. 65 - 15 = 50.)
60 -20 = 40
20 + 40 = 60
45 says in my math book
20,40,60 Proof (20)(20/4=5)(20/5=4)(20/10=2) And (40)(40/4=10)(40/5=8)(40/10=4) And (60)(60/4=15)(60/5=12)(60/10=6)
The factors of 40 are: 1, 2, 4, 5, 8, 10, 20, 40 The factors of 60 are: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60
Factors of 40: 1, 2, 4, 5, 8, 10, 20, 40.Factors of 80: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80.Factors of 60: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60.GCF (40, 80, 60) = 20
25
The GCF is 20.
The LCM of 15 and 20 is 60. That is the multiple of the combined prime factors of both numbers (2 x 2 x 3 x 5).The multiples of 15 are 15, 30, 45, 60, and so on. The multiples of 20 are 20, 40, 60, and so on. Thus 60 is the first number that can be made from multiples of both 15 and 20.Least Common Multiple (LCM) for 15 20 is 6060
The factors of 40 are: 1, 2, 4, 5, 8, 10, 20, 40The factors of 60 are: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60
20 / 4 = 5 20 / 5 = 4 40 / 4 = 10 40 / 5 = 8 60 / 4 = 15 60 / 5 = 12 80 / 4 = 20 80 / 5 = 16 Therefore, the numbers are 20, 40, 60, 80, and so on.
The multiples of 20 are 20, 40, 60, 80, 100, 120... The multiples of 30 are 30, 60, 90, 120, 150... The multiples of 15 are 15, 30, 45, 60, 75, 90, 105, 120, 135... The common multiples of 20, 30, and 15 are 60, 120, 180, 240...