Answer:
14
Step-by-step explanation:
Let's say Devaughn is x amount of years old and Sydney is y amount of years old.
Since the sum of their age is equal to 56, you would make the equation:
x+y=56
Now, set that aside and move on to the next step.
They are saying the Devaughn (x) is 3 times the number of years Sydney (y) is. So in mathematical terms you can create an equation stating:
3y=x because 3 times Sydney's age (y) would be Devaughn's age (x).
With the equations:
3y=x
x+y=56
You can plug in x in (x+y=56) as 3y because the other equation is saying that x is equal to 3y. So, that will give you 3y+y=56. Now, combine like terms or just simplify.
Simplifying 3y+y=56 would give you 4y=56, now just divide 56 by the 4 and you will get 14. This is saying that y=14. Now plug in y for the other equation (x+y=56):
x+14=56
Subtract 56 by 14 and it'll give you 42. That is saying x=42.
The question is asking for Sydney's age and i substituted her for the letter y which equaled 14.
Hope this helped :)
Answer:
57/41
Step-by-step explanation:
41 * x = 57
x = 57/41
Answer:
The percent of the pairs that last longer than six months—that is, 180 days is 95.637%
Step-by-step explanation:
Mean = xbar = 208 days
Standard deviation = σ = 14
The standardized score for 180 days is the value minus the mean then divided by the standard deviation.
z = (x - xbar)/σ = (180 - 208)/14 = - 1.71
To determine the percent of boots that last longer than 180 days, we need this probability, P(x > 180) = P(z > (-1.71))
We'll use data from the normal probability table for these probabilities
P(x > 180) = P(z > (-1.71)) = 1 - P(z ≤ (-1.71)) = 1 - 0.04363 = 0.95637 = 95.637%
Answer:
Step-by-step explanation:
Since ABC is an equilateral triangle, thus AB=BC=AC=x, therefore
The perimeter of ΔABC=36
⇒AB+BC+AC=36
⇒x+x+x=36
⇒3x=36
⇒x=12
Thus, AB=BC=AC=12.
Now, Since ΔADC is isosceles triangle, therefore AD=DC=y.
Perimeter of ΔADC=40
⇒AD+DC+CA=40
⇒x+y+y=40
⇒12+2y=40
⇒2y=28
⇒y=14
Therefore, AD=DC=14
Thus, Length of sides of ΔABC are AB=BC=AC=12 and Length of sides of ΔADC are AD=DC=14.
Answer:
<u>C</u>
Step-by-step explanation:
Evaluating the options :
<u>Option A</u>
⇒ 5/2x + 7/2 = 3/4x + 14
⇒ 2.5x - 0.75x = 14 - 3.5
⇒ 1.75x = 10.5
⇒ x = 6
⇒ No ×
===========================================================
<u>Option B</u>
⇒ 5/4x - 9 = 3/2x - 12
⇒ 1.5x - 1.25x = -9 + 12
⇒ 0.25x = 3
⇒ x = 12
⇒ No ×
=========================================================
<u>Option C</u>
⇒ 5/4x - 2 = 3/2x - 4
⇒ 1.5x - 1.25x = -2 + 4
⇒ 0.25x = 2
⇒ x = 8
⇒ Yes √
<u>C</u> is the right answer.