Talia tossed a penny many times. she got 40 heads and 60 tails. she said the experimental probability of getting heads was 40/60. explain and correct her error.

The more times you do a test, the more accurate the results will be.

Since there are only 2 options/sides the probability should be 1/2 for both heads and tails. 

Her error was both mathematical (her experimental probability number didn't make sense) and her lack of sufficient testing.