Answer:
Explanation:
The first one :
3/10 + 4/14 = 3.7/10.7 + 4.5/14.5 = 21/70 + 20/70 = (21+20)/70 = 41/70
The first step is, to make the 2 denominators of the 2 fractions to be the LCM.
10 = 2.5
14 = 2.7
So, the LCM of these 2 will be 2.5.7 = 70
In 3/10, we multiply both the nominator and the denominator by 7 to make the denominator 70.
And in 4/14, we multiply both the nominator and the denominator by 5 to make the denominator 70
And so we have : 21/70 + 20/70
Add the nominators together, the denominator stay the same, we'll have 41/70.
The second one : 5/12 = 6/13 = 5.13/12.13 - 6.12/13.12 = 65/156 - 72/156 = (65-72)/156 = -7/156
So, we find the LCM of 12 and 13 again. And since 13 is a prime number and 12 is not a factor of 13, the LCM will be 12x13=156
Multiply both the nominator and the denominator of 5/12 by 13, and 6/13 by 12, we'll get 65/156 and 72/156
Subtract the nominators, the denominator stay the same, we get -7/156.