23 + d = 71. ———————————————————-
Answer:
The reading speed of a sixth-grader whose reading speed is at the 90th percentile is 155.72 words per minute.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
What is the reading speed of a sixth-grader whose reading speed is at the 90th percentile
This is the value of X when Z has a pvalue of 0.9. So it is X when Z = 1.28.
The reading speed of a sixth-grader whose reading speed is at the 90th percentile is 155.72 words per minute.
Answer:
Step-by-step explanation:
In a geometric sequence, the consecutive terms differ by a common ratio,r. Considering the given sequence,
r = 6/- 2 = - 18/6 = - 3
Therefore, the sequence is geometric.
The formula for determining the nth term of a geometric progression is expressed as
Tn = ar^(n - 1)
Where
a represents the first term of the sequence.
r represents the common ratio.
n represents the number of terms.
From the information given,
a = - 2
r = - 3
The explicit formula is
Tn = - 2 × (- 3)^(n - 1)
To find the 8th term, T8,
T8 = - 2 × (- 3)^(8 - 1)
T8 = - 2 × (- 3)^7
T8 = - 2 × - 2187
T8 = 4374
For this you use A=Pe^(rt)
A=furutre amount
P=present amount
e=natural base
r=rate in decimal
t=times in years
A=?
P=5000000
r=0.04
t=30
A=5,000,000e^(0.04*30)
A=5,000,000e^(1.2)
A=16600584.613683
Answer:
Venus fly trap = 12
Bonsai tree = 17
Step-by-step explanation:
Given that :
Venus fly trap = $3per plant
Bonsai tree = $5 per plant
Number of plants sold = 29
Total cost of plant sold = $121
Let venus fly trap = x ; bonsai tree =y
x + y = 29 ___ (1)
3x + 5y = 121 ____(2)
From (1) :
x = 29 - y
In (2):
3(29 - y) + 5y = 121
87 - 3y + 5y = 121
87 + 2y = 121
2y = 121 - 87
2y = 34
y = 34/2
y = 17
x = 29 - 17
x = 12
Hence,
Venus fly trap = 12
Bonsai tree = 17
