The order of operations says:
P arentheses
E xponents
M ultiplication
D ivision
A ddition
S ubtraction
So first we will do 3 x 9 = 27. (27 - 6 + 3 / 10)
Next do 3/10 = .3. (27 - 6 + .3)
Then solve 27-6 = 21. (21 + .3)
Lastly do the last part! The answer is 21.3, hope this helps!
Answer:
1, 2, 6
Step-by-step explanation:
The z score shows by how many standard deviations the raw score is above or below the mean. The z score is given by:

Given that mean (μ) = 130 texts, standard deviation (σ) = 20 texts
1) For x < 90:

From the normal distribution table, P(x < 90) = P(z < -2) = 0.0228 = 2.28%
Option 1 is correct
2) For x > 130:

From the normal distribution table, P(x > 130) = P(z > 0) = 1 - P(z < 0) = 1 - 0.5 = 50%
Option 2 is correct
3) For x > 190:

From the normal distribution table, P(x > 3) = P(z > 3) = 1 - P(z < 3) = 1 - 0.9987 = 0.0013 = 0.13%
Option 3 is incorrect
4) For x < 130:

For x > 100:

From the normal table, P(100 < x < 130) = P(-1.5 < z < 0) = P(z < 0) - P(z < 1.5) = 0.5 - 0.0668 = 0.9332 = 93.32%
Option 4 is incorrect
5) For x = 130:

Option 5 is incorrect
6) For x = 130:

Since 1.5 is between 1 and 2, option 6 is correct
answer = 9c²d^8
(3cd^4)^2
=(3)^2 × c^2 × (d^4)^2
=9×c^2×d^8 ----law of indices (a^m)^n = a^mn
=9c²d^8
Joanna bought 7 notebooks and 14 pencils
Step-by-step explanation:
Step 1 :
Let x denote the number of notebooks and y denote the number of pencils Joanna bought.
Cost of one notebook = $ 2.30
Cost of one pencil = $1.42
Step 2 :
Total of notebooks and pencils bought = 21
=> x + y = 21 => y = 21-x
Total cost of notebooks and pencils = $35.98
=> 2.3x + 1.42y = 35.98
Substituting y = 21- x here , we have,
2.3x + 1.42 ( 21-x) = 35.98
2.3x + 29.82 - 1.42x = 35.98
0.88 x = 6.16
=> x = 7
y = 21-x = 21-7 = 14
Step 3 :
Answer :
Joanna bought 7 notebooks and 14 pencils
Answer:
x=20
Step-by-step explanation:
Well just cross multiply if its easier
x(3)=3x
12*5=60
60=3x
x=20