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(7, 6) = 42. In practice, it is enough to find the common denominator (not necessarily the lowest) by multiplying the denominators: 7 × 6 = 42. In the next intermediate step , cancel by a common factor of 2 gives 1121.
