You may go the super easy way and choose 1 as the whole number and 0.28 as the decimal number. Then you'd obviously have 
Otherwise, to be a bit more creative, you can observe that

And since 1/25=0.04, you can also choose 7 as the integer, and 0.04 as the decimal to get

1. 0.3% or 30%
2. 15 minutes
3. 48 times
The answer for x is:
x= 0.7-0.83 = -0.13