Answer
arrange the element in increasing order
-1.9, -1.3, -0.8, 2.3, 5.8, 7.4, 8.5, 9.9
interquatile = Q3 - Q1
We have five value in the data-set
The third value will be 10 since we want the median to be 10
We want the mean to be 14
To find the mean of a data set, we divide the sum of the values by the number of values
Mean = Sum of values ÷ Number of values
14 = Sum of values ÷ 5
Sum of values = 14 × 5
Sum of values = 70
So we need 5 values that add up to 70, one of the value is 10, which is the median. We would want two values that are smaller than 10 and two values more than 10.
These four value must add up to 70 - 10 = 60
From here we can do trial and error:
Choose any two values less than 10, say 9 and 8
We now have in total 8 + 9 + 10 = 27
We have 70 - 27 = 43 left to find
Choose any two values that are bigger than 10 that add up to 43, for example, 20 and 23
Now we have our 5 values;
8 9 10 20 23
Do the checking bit:
We can see from the set, the median is 10
Mean = [8+9+10+20+23] ÷ 5 = 70 ÷ 5 = 14
We can have values other than 8, 9, 20 and 23 as long as two values smaller than 10 and two values more than 10. All five values must add up to 70.
We are given with three equations and three unknowns and we need to solve this problem. The solution is shown below:
Three equations are below:
3x + 4y - z = -6
5x + 8y + 2z = 2
-x + y + z = 0
use the first (multiply by +2) and use the second equation:
2 (3x+4y -z = -6) => 6x + 8y -2z = -12
+ ( 5x + 8y +2z = 2)
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11x + 16y = -10 -> this the fourth equation
use the first and third equation:
3x + 4y -z = -6
+ (-x + y + z =0)
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2x + 5y = -6 -> this is the fifth equaiton
use fourth (multiply by 2) and use fifth (multiply by -11) equations such as:
2 (11x + 16y = -10) => 22x + 32y = -20 -> this is the sixth equation
-11 (2x + 5y = -6) => -22x -55y = 46 -> this is the seventh equation
add 6th and 7th equation such as:
22x + 32y = -20
+(-22x - 55y = 66)
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- 23y = 46
<span> y = -2
solving for x, we have:
</span>2x + 5y = -6
2x = -6 - 5y
2x = -6 - (5*(-2))
2x = -6 +10
2x = 4
x=2
solving for y value, we have:
-x + y + z =0
z = x -y
z = 2- (-2)
z =4
The answers are the following:
x = 2
y = -2
z = 4
The answer is c ≥ 1
Subtract 10 on both sides.
11-10= 1
and that’s how u get ur answer, hope this helped :)
