Answer:
Step-by-step explanation:
Find the midpoint of each frequency range, multiply that number by the frequency, sum up and divide by the total frequency.
This will give the mean number.
<u>The mean is:</u>
- [17*( 3 + 3.5)/2 + 21*(3.5 + k)/2 + 33*(k + 4)/2 + 54*(4 + 4.5)/2 + 15*(4.5 + 6)/2]/140 = 4.09
- 55.25 + 10.5k + 36.75 + 16.5k + 66 + 229.5 + 78.75 = 140*4.09
- 17k + 466.25 = 572.6
- 17k = 572.6 - 466.25
- 17k = 106.35
- k = 106.35/17
- k = 6.26
Note, I expected the value of k between 3.5 and 4. This is a bit of illogical outcome.
Answer:
21- two rupee coins
7- five rupee coins
Step-by-step explanation:
3x(2)=5x
6x=5x
6x+5x=77
11x=77
x= 7
thus 3x(2)means she has 21-2 rupee coins and 7-5rupee coins.
Answer:
39
Step-by-step explanation:
Let a and b represent the first and second digits, respectively.
... a = b -6 . . . . . . the first digit is 6 less than the second
... a + b = 12 . . . . .the sum of digits is 12 (an even number)
Using the expression in the first equation, we can substitute for a in the second equation:
... (b -6) +b = 12
... 2b = 18 . . . . . . add 6, simplify
... b = 9 . . . . . . . . .divide by 2
... a = 9 -6 = 3 . . . . from the first equation
The number is 39.
Start on -4 and go forward 6.
-4+6=2
