Question

1/7 - 20/21

Answer 1

-17/21

Answer 2

(1/7)-(20/21)=
(3/21-20/21) =
-17/21

Answer 3

how did you do it

Answer 4

ok you have to make like bases

1/7 has a denominator of 7 and 20/21 has a denominator of 21

both 7 and 21 have a LCM, which happens to be 21

(7x3=21 and 21x1=21)

so we want the denomoinator to be 21

so in order to get 1/7 to ?/21, we have to multiply by 3/3 (which is "1" in disguise, so its allowed)

that gets us (1x3)/(7x3)= 3/21

not that we have 3/21 and 20/21, we can subtract the top part of the fraction and leave the bottom part

3/21-20/21 = (3-20)/21= -17/21

does this help?

Answer 5

yes think you i jus got finished copying it

Answer 6

?