Answer:
30 ft
Step-by-step explanation:
This is a classic right triangle problem, where the length of the ladder represents the hypotenuse, where the ladder is lengthwise from the building is the base of the triangle, and what we are looking for is the height of the triangle. Pythagorean's Theorem will help us find this length.
so
1024 - 100 = y^2 and
y = 30.4 so 30 feet
Answer: E. 120
The number of seniors were there in high school X at the beginning of the year = 120
Step-by-step explanation:
Given : At the beginning of the year, the ratio of juniors to seniors in high school X was 3 to 4.
Let the number of juniors be 3x and the number of seniors be 4x.
Since , during the year, 10 juniors and twice as many seniors transferred to another high school, while no new students joined high school X.
i.e. Number of juniors at the end of the year = 3x-10
Number of seniors at the end of the yea = 4x-2(10)=4x-20
At the end of the year, the ratio of juniors to seniors was 4 to 5.
The number of seniors were there in high school X at the beginning of the year = 4(30)=120
Hence, the correct answer is E. 120 .