Answer:
-2x + 3
Step-by-step explanation:
-5x/5 - 20/5 - 4x/4 + 28/4 ➡-x - 4 -x +7 ➡-2x + 3
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: 8 1/3 hours or 500 minutes
Step-by-step explanation:
Keep in mind that there are 100 centimeters in a meter.
The snail moves at a pace of 12 cm/h, and needs to go 100 cm. You can just divide 100/12 to get 8 1/3, which is how many hours (groups of 12 cm) it takes for the snail to travel 100 cm (1 meter).
If necessary, you can also multiply 8 1/3 by 60 to get the number of minutes the snail takes. 8 times 60 is 480, and 1/3 of an hour is 20, so add 480+20 to get 500 minutes.
Answer:
155.093
Step-by-step explanation:
(Thousands place is underlined)
155.09<u>2</u>71
Since 7 is bigger than 5, you round the 2 to a 3
155.09<u>3</u>
