Calculate 3/5 + 5/8. Give your answer as a mixed number in its simplest form.

To answer this question, create the least common denominator possible. In this instance, the LCD is 40. (I know this because multiples of 5 only end in 0 and 5, and 40 is the lowest multiple of 8 that meets this criteria). To change each fraction I carried out the following equations: 3/5 x 8/8 = 24/40, 5/8 x 5/5 = 25/40. I then added the two together: 24/40 + 25/40 = 49/40. As the question asks the answer to be given as a mixed number in its simplest form, I then change this to 1 9/40. I know that this cannot be simplified as 9 is only divisible by 1,9 and 3. 40 is not divisible by any of those and so this is the simplest form of the fraction.