What is 30% of $40 is

  $12

Step-by-step explanation:

"Of" means "times" in this context:

  30% × $40 = 30/100 × $40 = $12

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% is a fancy way to write /100, so 30% = 30/100 = 0.30 (thirty hundredths).

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Since you're familiar with decimal multiplication, you know that you can rewrite this problem as ...

   30/100 × $40

   = 3/10 × $40

   = 3 × ($40/10)

   = 3 × $4

   = $12

addition

step-by-step explanation:

i get you, what you should do is think of the positive things that would come out of it. it will make yours parents proud and raise your grade. you should always try and if you can't focus tell the teacher.