Answer:
B. 
Step-by-step explanation:
Using Pythagorean theorem, find the value of x.
Pythagorean theorem is given as 
Where,
c is the longest side of a right angled ∆ = the hypotenuse = x
a and b are legs of the right angled ∆ = 2 and 6
Plug in the values into the equation and solve for x
has ten elements, so any proper subset has at most nine of these elements.
The number of ways of taking any
letters from this set is given by the binomial coefficient,
and in particular, the total number of ways to picking proper subsets is
Without computing each term directly, let's instead use a direct result from the binomial theorem, which says
If we replace
, then we're left with
We can use this to evaluate our sum directly:
Not sure what you are looking for, but the difference between $67.44 & the monthly fee of $17 would be the cost of the charge of minutes he spent talking on the phone. 67.44 - 17.00 = $50.44
50.44/ .04 = 1,261 minutes he talked on the phone.
Answer:
Step-by-step explanation:
let X be the quantity of 100% acid
let Y be the quantity of 10% acid
X + Y = 90
Y = 90 - X
X(100) + Y(10) = 90(81)
X(100) + (90 - X)(10) = 90(81)
100X + 900 - 10X = 7290
90X = 6390
X = 71 L
