Answer: 36%
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Step-by-step explanation:
There are 20 blue cards out of 10+20+25 = 55 cards total.
Divide the 20 over 55 to get
20/55 = 0.363636...
where the "36"s go on forever
So 20/55 = 0.3636 approximately
Move the decimal point over 2 spots to go from 0.3637 to 36.37%
Then round to the nearest percent: 36.37% ---> 36%
The probability of getting a blue card is approximately 36%