38.25 is the average
The way you do it is...add all the numbers, then divide that number by the numbers of numbers you just added.
65+49+24+15=153
153/4=38.25
38.25
38.25
38.25
38.25
Average = sum/number = 153/4 = 38.25
16 + 49 = 65
49/65 x 100 = 75.384615 recurring (that is, 75.384615384615...) percent.
Since the two numbers are coprime, LCM(65, 49) = 65*49 = 3185
LCM of 49 and 99 and 65 is 315315.
-15+3
To find 24 percent of a number, multiply it by 0.24. In this instance, 65 x 0.24 = 15.6, or 15 and three fifths.
For 13/24 and 7/15 the common denominator is 120. So we have: (13 x 5)/(24 x 5) and (7 x 8)/(15 x 8) 65/120 and 56/120 (which are equivalent respectively to 13/24 and 7/15). Since 65/120 > 56/120, so is 13/24 > 7/15.