Answer:
The mean = 17.54
Step-by-step explanation:
Form a table as below;
<u>Interval Frequency{f} Midpoint of frequency{x} fx </u>
1-7 19 4 76
8-10 14 9 126
11-15 15 13 195
16-20 20 18 360
21-35 10 28 280
36-50 13 43 559
Sum 91 1596
The mean of grouped data = Sum of { Interval Midpoint * Frequency } /Sum of frequency
The mean= 1596 / 91
The mean = 17.54
Think: You're treating the numerator and the denom. in precisely the same way. In doing so you are NOT changing the value of the fraction, only the appearance.
Example: start with 2/3. Mult num. and den. both by 7: 14/21.
2/3 and 14/21 result in precisely the same decimal fraction, showing that the latter set of fractions is equivalent to the former set.
So,
The secret to solving problems with ratios is to find the value of one unit.
5:7 = 12 units total
To find one unit, divide the total number of students by the total number of units.
600/12 = a
Simplify
50/1 = a
50 = a
The value of each unit is 50.
Now, multiply the units by the numbers in the ratio.
50(5) = b
250 = boys
50(7) = x
350 = x
There are 350 girls.
Answer:
y=10x+10
Step-by-step explanation: