What percent is of 30 is 40

30/x=100/40

(30/x)*x=(100/40)*x       - you multiply both sides of the equation by x

30=2.5*x       - you divide both sides of the equation by (2.5) to get x

30/2.5=x  

12=x  

x=12

now we have:  

40% of 30=12

Step-by-step explanation:

step-by-step explanation:

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