Answer:
Option C is correct.
f = 2
Step-by-step explanation:
The mean is the sum of variables divided by the number of variables
Mean = (Σfx)/(Σf)
xi | 15 | 17 | 20 | 30 | 10 + f
fi | 4 | 4 | 6 | 5 | 6
Σfx = (15×4) + (17×4) + (20×6) + (30×5) + [(10+f)×6] = 60 + 68 + 120 + 150 + 60 + 6f = (458 + 6f)
Σf = 4 + 4 + 6 + 5 + 6 = 25
Mean = 18.8
18.8 = (458+6f) ÷ 25
458 + 6f = 25 × 18.8 = 470
6f = 470 - 458 = 12
f = (12/6) = 2
Hope this Helps!!!
Answer:
c
Step-by-step explanation:
i had this problem before so i know
Answer:
19%
Step-by-step explanation:
Last year:
Number of boys on honor roll = 96
Number of girls on honor roll = 60
Total students on honor roll = Number of boys on honor roll + Number of girls on honor roll
= 96 + 60
= 156
This year:
The number of boys on the honor roll increased by 25%
Number of boys on honor roll = 25% of 96 + 96
= 0.25×96 + 96
= 24 + 96
= 120
The number of girls on the honor roll increased by 10%.
Number of girls on honor roll = 10% of 60 + 60
= 0.10 × 60 + 60
= 6 + 60
= 66
Total students on honor roll = Number of boys on honor roll + Number of girls on honor roll
= 120 + 66
= 186
Percentage the total number of students on the honor roll increase = (186 - 156) / 156 × 100
= 30 / 156 × 100
= 0.19 × 100
= 19% to the nearest tenth
Answer:
C
Step-by-step explanation:
the correct answer is C
Step-by-step explanation:
3a²-7a−6
Factor the expression by grouping. First, the expression needs to be rewritten as 3a
2
+pa+qa−6. To find p and q, set up a system to be solved.
p+q=−7
pq=3(−6)=−18
Since pq is negative, p and q have the opposite signs. Since p+q is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product −18.
1,−18
2,−9
3,−6
Calculate the sum for each pair.
1−18=−17
2−9=−7
3−6=−3
The solution is the pair that gives sum −7.
p=−9
q=2
Rewrite 3a
2−7a−6 as (3a
2−9a)+(2a−6).
(3a 2−9a)+(2a−6)
Factor out 3a in the first and 2 in the second group.
3a(a−3)+2(a−3)
Factor out common term a−3 by using distributive property.
(a−3)(3a+2)