Answer:
20
Step-by-step explanation:
It seems like the rule of this sequence is to add 5 (since 2 + 5 = 7 and 7 + 5 = 12). We already are given that we have 2 2-digit numbers (12 and 17) so let's see if there are any more. The sequence continues to 22, 27, 32, 37, 42, 47, ..., 92, 97. We need to count how many numbers are in the list 12, 17 ... 92, 97. To do this, let's add 3 to every term in the list to get 15, 20, ... 95, 100. Since the list is now full of multiples of 5 we can divide the list by 5 to get 3, 4, ... 19, 20 and then subtract 2 to get 1, 2, ... 17, 18 which means that there are 18 2-digit numbers.
Answer:
m∠B = 31°
Step-by-step explanation:
First, find the measure of angle ACB by subtracting its supplement from 180 degrees:
180 - 113 = 77
m∠ACB = 77°
Then subtract both m∠A and m∠ACB from 180 degrees, since the interior angles of a triangle always add to 180°:
m∠B = 180° - 72° - 77°
m∠B = 31°