What is the value of the expression 1/2-(-1/3 + 2/5)?

Answer:
13/30
Step-by-step explanation:
Add: -1/
3
+ 2/
5
= -1 · 5/
3 · 5
+ 2 · 3/
5 · 3
= -5/
15
+ 6/
15
= -5 + 6/
15
= 1/
15
For adding, subtracting, and comparing fractions, it is suitable to adjust both fractions to a common (equal, identical) denominator. The common denominator you can calculate as the least common multiple of the both denominators - LCM(3, 5) = 15. In practice, it is enough to find the common denominator (not necessarily the lowest) by multiplying the denominators: 3 × 5 = 15. In the next intermediate step the fraction result cannot be further simplified by canceling.
In words - minus one third plus two fifths = one fifteenth.
Subtract: 1/
2
- the result of step No. 1 = 1/
2
- 1/
15
= 1 · 15/
2 · 15
- 1 · 2/
15 · 2
= 15/
30
- 2/
30
= 15 - 2/
30
= 13/
30
For adding, subtracting, and comparing fractions, it is suitable to adjust both fractions to a common (equal, identical) denominator. The common denominator you can calculate as the least common multiple of the both denominators - LCM(2, 15) = 30. In practice, it is enough to find the common denominator (not necessarily the lowest) by multiplying the denominators: 2 × 15 = 30. In the next intermediate step the fraction result cannot be further simplified by canceling.
In words - one half minus one fifteenth = thirteen thirtieths.