John was adding Rational Numbers. He showed his work below. What was John's error? Explain to John how to solve it correctly.

Adding Rational Numbers Error.

-5 3/5

Step-by-step explanation:

John's error was in adding the whole number and fractional portions separately, the fractions must be converted to improper fractions with common denominators to be added or subtracted properly so

(-7 4/5) + (2 1/5), convert to improper fractions

-39/5 + 11/5, both fractions have common denominator so we can continue

-39 + 11 = -28, so -39/5 + 11/5 = -28/5, convert back to proper fractions

-28/5 = (-25/5) + (-3/5) = -5 3/5

well there are two answers for that.

1: you need 120 ones then that will equal up to 120.

2: you could also do one 100 and 2 tens.

those are the answers that i have thought of.