Find Common Denominator: Compare the two fractions by finding a common denominator. The denominators are 8 and 2. The least common multiple (LCM) of 8 and 2 is 8. Convert 21 to a fraction with denominator 8: (21)∗(44)=84.
Convert 21 to 84: Now, compare 81 and 84. Since 1 is less than 4, 81 is smaller than 84.