Math
posted by Patricia .
Tina owned 4/5 of the family business. She sold 1/2 of the business to her son. What portion of the business does she still own?

2/5

Subtract 5 7/10 minus 3 14/15

4/5  1/2
Find a common denominator and solve. 
4/5  1/2
common denominator is the number where they can both divide into equally, for this one, it would be 10. (5 x 2 = 10) (2 x 5 = 10), once you find a common denominator (preferably the lowest common multiple) you must multiply the denominator (with the number to create the common denominator)and the numerator (by the same number multiplied by the denominator). Therefore
4(x2)/5(x)  1(x5)/2(x5) =
8/10  5/10
= 3/10
(Note: Do not subtract the denominator, ONLY the numerator) 
Problem
0 4  0 1 5 2 10 is the common denominator for the fractions.4 * 2 + 1 * 5 5 2 2 5 Now the fractions have the same denominators and the numerators can be subtracted.8  5 10 10 Subtract the numerators.3 10