Because subtracting a negative number is the same as adding a positive number.
Subtracting -20 is the same as adding +20.
31 - (-20) = 31 + 20 = 51
31 and 20
2.55 times.
31 is prime, but 51 is not as 51=3*17.
The LCM of 31 and 51 is 1,581.
93
51
93
31/51 is in its simplest form.
20% of 51= 20% * 51= 0.2 * 51= 10.2
The rule is 5, 10, 15 and so the next number will be 20+31 = 51
51% = 51/100
Then A = 31, b = 31 and c = 31/15 = 2.066...