Answer: The average was 9 years old find the average age of both groups is 10 years old.
Step-by-step explanation:
Formula foe average : 
Given : The first group of students consists of 10 and their average age was 13 years old.
i.e.
(1)
The next group consisted of 30 students and their average was 9 years old.
i.e.
(2)
Then from (1) and (2) , the sum of both groups (first group and next group )students = 130+270 =400
Combined students of both groups (first and next group )= 10+30=40
Now , the average of both groups =

Hence, the average was 9 years old find the average age of both groups is 10 years old.
Answer:
5.236 units
Step-by-step explanation:
The relation between r, θ and arc length ( l ) is,
l = rθ
l = 1 * 5π / 3
( The value of π = 3.14 approximately )
5π = 5 x 3.14 = 15.7
l = 1 * 5π / 3
= 5π / 3
= 15.7/3
l = 5.236 units
Note : -
Arc length is denoted by " l ".
Answer:
2B/( h-q)=a
Step-by-step explanation:
2B=ha-qa
Factor out an a
2B=a(h-q)
Divide each side by ( h-q)
2B/( h-q)=a(h-q)/( h-q)
2B/( h-q)=a