Answer: She had 27.2% correct.
Step-by-step explanation: To find the percent, we can divide the part and whole then multiply the quotient by 100. After that we'll need to convert the percent to a decimal. In mathematical terms, the formula will be,

40% will be the part and 68% will be the whole.
Step 1.
Convert 40 into a decimal by dividing it by 100.
40 ÷ 100 = 0.4
Step 2.
Multiply 0.4 by 68.
0.4 × 68 = 27.2
Hence, she had 27.2% correct.