Answer: She's used 630 minutes.
Step-by-step explanation:
She has 1400 minutes.
She used 45% of them.
1. Convert 45% to decimals. You can do by dividing by 100.
[tex]\frac{45}{100}=0.45[/tex]
2. Multiply by the total amount of minutes.
[tex]0.45(1400)=630[/tex]