Math
posted by sarah .
Compute the area of a triangle with a base of 15 cm and an altitude of 10.5 in.
Area (to the nearest tenth) = cm2
I plugged everything into the area formula which is A = (1/2)bh .
A=.5x15x10.5= I got 78.75 rounded 78.8.
The computer keeps saying I am wrong. What am I doing wrong?

Looks good to me. Computer may have wrong answer. Better check with your instructor. Have you tried entering 78.7 just in case they rounded wrong?

If your data are correct, I don't see anything you are doing wrong.

Aha! Note that the area is
(1/2)(15 cm)(10.5 in)
= (1/2)(15 cm)(26.67 cm)
= 200.0 cm^2
Gotta watch those units!
Not a trick question, but ... 
How did you get 26.67?

you gotta know that
1 in = 2.54 cm 
Omg Thank you !! I now know how to solve this type of problem the correct way ! Thank you so much !

Sorry that I missed the difference in units.
10.5 inches = 26.67 cm.