David's score on his fifth test would be an 87. If you add up all the scores from his first to his fourth test, it would 363. However, since there are five tests, in order to get a 90 percent, the sum of all five test scores would be 450. 450 - 363 = 87.
Answer:
1.25.
Step-by-step explanation:
The common ratio r is 1/5 and the first term a1 = (1/5)^(1-1) = 1.
Sum to infinity = a1 / (1 - r)
= 1 / (1 - 1/5)
= 1 / 4/5
= 5/4
= 1.25 (answer)
The correct answer is A) yes, the sum of each pair is greater than the third.
The triangle inequality theorem states that the sum of any two sides of a triangle is longer than the third side. This is true for these numbers, so this does form a triangle.
