Answer:
9
Explanation:
To solve, we can first cross multiply
28/63=4/x
28*x=63*4
28x=252
Since we are trying to find x(the missing number), we need to get x by itself. x is being multiplied by 28. To undo this, divide both sides by 28. This will cancel out 28 and leave x by itself.
28x/28=252/28
x=9
So, the missing number is 9
28/63=4/9