10/7 - 149/140 =
First, find the least common denominator (bottom numbers)
7 and 140 =
LCM = 140
Multiply the top and bottom number od the first fraction by 20
[tex](\frac{10}{7}\times\frac{20}{20})-\frac{149}{140}[/tex][tex]\frac{200}{140}-\frac{149}{140}[/tex]Now that both fractions have the same denominator (140) simply subtract the top numbers
[tex]\frac{(200-149)}{140}[/tex][tex]\frac{51}{140}[/tex]