30% of a number is 7.5 can be written as an equation.
30% can be rewritten as 0.30, or even 0.3.
a number can be written as "x".
So far, we have 0.3x.
"is" is a keyword for "equal".
0.3x=
It says "is 7.5".
0.3x=7.5
We can solve this equation.
0.3x=7.5
/0.3 /0.3
x=25
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hope it helps
