Answer:
3 student.
Step-by-step explanation:
From the first statement:
Let the total score be T
Let the total number of student be x
The average of the score = 72
Average = Tota score / number of student
72 = T/x
Cross multiply
T = 72x ..... (1)
Second statement:
One more student took the test and the average becomes 76 with the student having a score of 88.
Therefore,
Overall score = T + 88
Total student = x + 1
Average = 76
Average = overall score / total number of student
76 = (T + 88) /(x + 1)
Cross multiply
76(x + 1) = T + 88
Clear bracket
76x + 76 = T + 88
From equation 1
T = 72x
76x + 76 = 72x + 88
Collect like terms
76x – 72x = 88 – 76
4x = 12
Divide both side by the coefficient of x i.e 4
x = 12/4
x = 3
Therefore, the initial number of the student were 3.
Answer:
126
Step-by-step explanation:
A Nonagon has 9 sides. To answer this, the polygon has to be regular.
The Perimeter is 9*14 = 126
Answer:
x = 10
Step-by-step explanation:
8 + 12 = 2x
8 + 12 = 20
20 = 2x
---- -----
2 2
10 = x
x = 10
Answer:
area = 21 feet^2
Step-by-step explanation:
Area of a triangle is 1/2(base*height)
1/2(6*7) = area
1/2(42) = area
area = 21 feet^2