6 2/3 x 3 1/3 x 5 1/4

116 2/3

Step-by-step explanation:

Turning each of them to improper fraction, we have

6 2/3 =20/3

3 1/3= 10/3

5 1/4= 21/4

Multiply them

20/3 times 10/3 times 21/4

We have 350/3

Turning it back to a mixed fraction, we have

116 2/3

Because 350/3 is 116 remainder 2.

c.

step-by-step explanation:

she should of added 9^2 and 12^2. that is because it is a^2+b^2=c^2. c^2 is the hypotenuse and should always be bigger than the other two numbers. which is why she should of added 9 squared and 12 squared together instead of 15 squared.