X= 103
180 - 65 = 115
X + 12 = 115
X = 115 - 12 = 103
Step-by-step explanation:
the beginning number is the beginning of your range the last number is the end of your range
Average of 10 people = 65
65 × 10 = 650
average of 5 people = 35
35 × 5 = 175
650 + 175 = 825
825 ÷ 15 = 55
the average reading time for the entire book club each day is 55 minutes a day
