Answer:
49
Step-by-step explanation:
4 : 3
x : 21
ok so we can divide 21 by 3 and get 7.
7 × 4 = 28
4 : 3 = 28 : 21
now we just 28 + 21 = 49 :D
Answer: 271
Step-by-step explanation:
The formula we use to find the sample size is given by :-

, where
is the two-tailed z-value for significance level of 
p = prior estimation of the proportion
E = Margin of error.
If prior estimation of the proportion is unknown, then we take p= 0.5 , the formula becomes


Given : Margin of error : E= 0.05
Confidence level = 90%
Significance level 
Using z-value table , Two-tailed z-value for significance level of 

Then, the required sample size would be :

Simplify,

Hence, the required minimum sample size =271
Answer:
arc AB = 70°
arc BC = 110°
arc ABC = 180°
arc CDB = 250°
Step-by-step explanation:
Since these angles are not inscribed, but are at the center point of the circle, the angles and arcs will be the same measure.
Solve for arc AB:
Angle AFB = 70°, so arc AB = 70°
Solve for arc BC:
Angle AFC is a straight angle so it is 180°. To find angle BFC, subtract angle AFB from 180°.
180 - 70 = 110°
Since angle BFC = 110°, arc BC = 110°
Solve for arc ABC:
Add arc AB and arc BC together.
70° + 110° = 180°
arc ABC = 180°
Solve for arc CDB:
There are 360° in a cirlce. To find arc CDB, subtract arc BC from 360°.
360° - 110° = 250°
arc CDB = 250°
Answer: 20 hours
Step-by-step explanation:
Equation: 15x = 300
Isolate the variable.
Divide both sides by 15: ¹⁵ˣ⁄₁₅ = ³⁰⁰⁄₁₅
x = 20
Ivan needs to work 20 hours in order to afford the bicycle.
Answer:
85.714%
Step-by-step explanation:
You are essentially solving for the percentage of 12/14. Divide:
12/14 = 0.85714
Change the decimal into a percentage by moving the decimal point to the right two place values:
0.85714 = 85.714%
85.714% is your answer.
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