Let x = number of adult tickets, and y = number of children tickets. One equation must deal with the number of tickets, and the other equation must deal with the revenue from the tickets.
Then x + y = 300 is the number of tickets
12x + 8y = 3280 is the revenue from the tickets.
Using the substitution method:
x + y = 300 ⇒ y = 300 - x ⇒ Equation (3)
12x + 8y = 3280 ⇒ 12x + 8(300-x) = 3280 ⇒ x = 220
y = 300 - x ⇒ y = 300-220 ⇒ 80
Therefore 220 adult tickets and 80 children's tickets were sold.
Answer:
4b^-1
Step-by-step explanation:
16a/4 = 4a
4a/a = 4
4/b = 4b^-1
Answer:
The straight line distance is 5 miles from starting point
Step-by-step explanation:
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.
Answer:
the answer is linear function lol