Question

what will come in the blank box in 1/7 + blank/21 = 1​

Answer 1

Answer:

18

Step-by-step explanation:

1/7+x/21=1

x/21=1-1/7

x/21=6/7

x=21*6/7

x=18

Answer 2

1/7 +18/21=1

so the answer is 18