P(z < x) = 0.6064 - 0.5 = 0.1064
From the normal distribution table
P(z < 0.27) = 0.1064
Therefore the z-score is 0.27
I can't explain it very well for you, sorry.
= [7+7 <span>÷ 7] + 4.12
= [7+1] + 4.12
= 8 + 4.12
= 12.12
</span>
10 >= 7 + 3x -4x+9<=1
-7 >= -7 - subtract 7 -9<=-9 - Subtract 9
__________ ___________
3 >=3x - divide by 3 -4x<=-8 - divide by -4
x>=1 x<=2
1/4 × 1/2 multiply 1/2 by 2 to get 2/4 then add 1/4 and 2/4 ur answer 3/4 the fraction of all the cookies that is peanut butter is 3/4
<span>let x = the original no. of students
then
(x+10) = the actual no. that went on the trip
:
= the original cost per student
and
= the actual cost
:
Original cost - actual cost = $12.50
- = 12.50
multiply equation by x(x+10)
x(x+10)* - x(x+10)* = 12.50x(x+10)
Cancel the denominators
1500(x+10) - 1500x = 12.5x(x+10)
1500x + 15000 - 1500x = 12.5x^2 + 125x
Combine on the right to form a quadratic equation
0 = 12.5x^2 + 125x - 15000
Simplify, divide equation by 12.5
x^2 + 10x - 1200 = 0
You can use the quadratic formula; a=1; b=10; c=-1200, but this will factor to
(x + 40(x - 30) = 0
The positive solution is what we want here
x = 30 students in the original group
Check this by finding the cost per student for each scenario
1500/30 = $50.00; original cost
1500/40 = $37.50; actual cost
---------------------
saving: $12.50</span>
