problem: fractions calculations add and subtract 1
Determine the lowest common denominator and calculate the value, reduce the solution and write as a mixed fractions if possible!
3/4 + 2/5 – 9/10 =
answer: fractions calculations add and subtract 1
the lowest common denominator:
4 = 2 * 2
5 = 1 * 5
10 = 2 * 5
2 * 2 * 5 = 20
calculate the value:
to make the bottom numbers the same you have to multiply the top and the bottom of
the first fraction with 5 (because 4 * 5 = 20)
the second fraction with 4 (because 5 * 4 = 20)
the third fraction with 2 (because 10 * 2 = 20)
3/4 + 2/5 – 9/10 =
3*5/4*5 + 2*4/5*4 – 9*2/10*2 =
15/20 + 8/20 – 18/20 =
23/20 – 18/20 = 5/20
simplify the solution with 5:
5:5/20:5 = 1/4