Answer :

2.8

= 2.0 + 0.8

= 2 + 4/5

= 10/5 + 4/5

= 14/5
2.8 = 2 + 0.8

*let's analyze the decimal 0.8 as a fraction

0.8 = 8/10

*but if we divide the numerator and denominator by the same common factor of 2, we find that the fraction can be reduced to:

(8/2)/(10/2) = (4)/(5) = 4/5

*now evaluating the whole value of 2 (from the 2.8), we know there are a total of (5) - fifths in order to make a whole, so for 2 whole, we require:

2*(5/5) = (2*5)/5 = 10/5

*Now we add the fractions together:

2 = 10/5
0.8 = 4/5

10/5 + 4/5

*add numerators only, the denominator stays as a 5

(10 + 4)/5 = 14/5

*there are no common factors between 14 & 5 (other than 1, but that won't help reduce the fraction any), so the fraction is in it's simplest form:

answer is: 14/5