Your answer should be 314
4 x 16=64
10 x 25 (25 is the height)=250
64 + 250=314
Answer:
k = -9
Step-by-step explanation:
subtract 2k from both sides
_5k+8= -37
subtract 8
_5k = -45
divide by 5
_k = -9
The final price is the cost plus the tax.
Since we know the tax and a percent, we can write this as
T = C(1+r)
T = what Graham paid = $87.45
C = cost before tax
r = tax rate expressed as a decimal = .40
Plugging in what we know
87.45 = C (1+.4)
87.45 = C(1.4)
Divide both sides by 1.4
C = $62.46
Answer:
3x-11
Step-by-step explanation:
f (x) = 3x - 5
f(x-2)
Replace x in the function with x-2
f (x-2) = 3(x-2) - 5
=3x-6 -5
=3x-11
Looks like a badly encoded/decoded symbol. It's supposed to be a minus sign, so you're asked to find the expectation of 2<em>X </em>² - <em>Y</em>.
If you don't know how <em>X</em> or <em>Y</em> are distributed, but you know E[<em>X</em> ²] and E[<em>Y</em>], then it's as simple as distributing the expectation over the sum:
E[2<em>X </em>² - <em>Y</em>] = 2 E[<em>X </em>²] - E[<em>Y</em>]
Or, if you're given the expectation and variance of <em>X</em>, you have
Var[<em>X</em>] = E[<em>X</em> ²] - E[<em>X</em>]²
→ E[2<em>X </em>² - <em>Y</em>] = 2 (Var[<em>X</em>] + E[<em>X</em>]²) - E[<em>Y</em>]
Otherwise, you may be given the density function, or joint density, in which case you can determine the expectations by computing an integral or sum.