Answer:336
Step-by-step explanation:
Considering that the square root of 9 is of 81 and of 10 is of 100, we have that the expression that has a value between 9 and 10 is given by:
B.) √89
E.) ![\sqrt[3]{750}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B750%7D)
F.) ![\sqrt[3]{999}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B999%7D)
<h3>How the square root of a number is used to solve this question?</h3>
We suppose numbers n and m, with square roots given, respectively, by n² and m².
Then, the square roots of all numbers between n² and m² have values between n and m.
In this problem, the square roots are given by:
Hence, the square root of all values between 82 and 99 are values between 9 and 10, thus option B is correct.
As for the cubic root, we apply the same logic and have that:
Hence options E and F are also correct, as the values between 730 and 999 have cubic roots between 9 and 10.
More can be learned about the value of a expression at brainly.com/question/25537936
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Answer:
Mean = 78.2
Standard deviation = 5.8
Step-by-step explanation:
Mathematically z-score;
= (x-mean)/SD
From the question;
12% of test scores were above 85
Thus;
P( x > 85) = 12%
P(x > 85) = 0.12
Now let’s get the z-score that has a probability of 0.12
This can be obtained from the standard normal distribution table and it is = 1.175
Thus;
1.175 = (85 - mean)/SD
let’s call the mean a and the SD b
1.175 = (85-a)/b
1.175b = 85 - a
a = 85 - 1.175b ••••••••(i)
Secondly 8% of scores were below 70
Let’s find the z-score corresponding to this proportion;
We use the standard normal distribution table as usual;
P( x < 70) = 0.08
z-score = -1.405
Thus;
-1.405 =( 70-a)/b
-1.405b = 70-a
a = 70 + 1.405b ••••••(ii)
Equate the two a
70 + 1.405b = 85 - 1.175b
85 -70 = 1.405b + 1.175b
15 = 2.58b
b = 15/2.58
b = 5.81
a = 70 + 1.405b
a = 70 + 1.405(5.81)
a = 78.16
So mean = 78.2 and Standard deviation is 5.8
flour : sugar = 8 : 2/3 = 24 : 2 = 12 : 1
OR in fraction form, you can write it as 12/1
