Let us assume the original cost of the earphones = x dollars
Then
x * (106/100) = 13.25
x = 13.25 * (100/106)
= 1325/106
= 12.50 dollars
So the actual cost of the earphones was $12.50. The correct option among all the options that are given in the question is the second option or option "B".
Okay so if $2 for the first 10 pounds, divide 10 by 2 and you get 5. every time you add a pound its a dollar more. so i think the answer is 45.
The correct answer is:
[C]: "
37, 680 mm³ " .
________________________________________________________
Explanation:
________________________________________________________
The formula for the volume, "
V" , o
f a cylinder is: → V =
* r² * h ;
→ in which "
r = length of radius" ; "
h = height" ;
________________________________________________________ {Note that the formula for the
volume, "
V" ,
of a cylinder is: → "
Base area * height " .
________________________________________________________ → Specifically, for a cylinder, the "Base area" is the area of a "circle", because the base is a circle;
→ and the formula for the "
area of a circle = [
tex] \pi [/tex] * r² " ;
→ in which "
r =
length of the radius" .
As such, t
he formula for the volume, "
V"
, of a cylinder is:______________________________________________________ → Volume = (Base area) * (height) ;
= (
r² ) * h ;
______________________________________________________
→ V =
r² h ;
in which: "
V = volume {in "
cubic units" ; or, write as "
units³ "
} ;
"
r = radius length" ;
"
h = height" ;
_____________________________________________________ → Now,
we shall solve for the volume, "
V", of the given cylinder in this question/problem:
_____________________________________________________ → V =
r² h ;
in which: "
r = radius = ? " ;
→ To find "
r" ; We are given the diameter, "d = 40 mm" ;
→ Note that:
"r = d/2 = (40 mm) / 2 = 20 mm " ;
{i.e., "the radius is half of the diameter".}.
→ "
r = 20 mm " ;
→ "
h = height = 30 mm " {given in figure) ;
→ For
; let us use "
3.14 " — which is a commonly used approximation.
→ For this question/problem, none of the answer choices are given "
in terms of 
" ;
→ so we shall use this
"numerical value" as an "
approximation" ;
_______________________________________________________Now, let us plug in our known values into the formula;
and calculate
to find the volume, "
V",
of our given cylinder;
as follows:_______________________________________________________
→ V =
r² h ;
= (3.14) * (20 mm)² * (30 mm) ;
= (3.14) * (20)² * (mm)² * (30 mm) ;
= (3.14) * (20)² * (30) * (mm³) ;
= (3.14) * (400) * (30) * (mm³) ;
= 37, 680 mm³
__________________________________________________
The volume is: "
37, 680 mm³ " ;
→ which is:
Answer choice [C]: "
37, 680 mm³ " .
___________________________________________________
Hope this answer and explanation—albeit lengthy—is of some help to you.
Best wishes!
1. Rename the mixed numbers with common denominators
2. Add the mixed numbers together to get 15 4/6
3. Subtract the sum from 26 to get 10 1/2
4. Since the only term left on the left is k so k=10 1/2
The formula for this is A= a + b/2 x h.