Answer:
-$0.16
Step-by-step explanation:
The expected value is the sum of the outcomes multiplied by their probabilities.
E(X) = 1/38 (+68) + 37/38 (-2)
E(X) = -0.16
Answer:
49x2−4y2
Step-by-step explanation:
7x(7x)+7x(−2y)+2y(7x)+2y(−2y)
Direct Proportion functions look like this:
y=kx
'k' is the constant of proportionality and in this case its 7.5 or 15/2.
--------------------------------------------
When x=1, y=7.5
When x=2, y=15
When x=3, y=22.5
Therefore y is directly proportional to x.
--------------------------------------
DIRECT PROPORTION EXPLAINED:
Say a football costs £7.50. If you buy one football you'll have to pay out £7.50, but if you you buy two footballs you'll have to pay out £15.00. Therefore the cost of the football(s) is directly proportional to the amount of footballs you buy. C=cost, f=football(s) and C<span>∝f, therefore C=kf, but as k=7.5, C=7.5f.
INVERSE PROPORTION EXPLAINED:
If it were to take 8 hours for one bricklayer to set up a wall, how long would it take for two bricklayers to set up a wall? The answer in this case would be 4 hours.
T=time to set up a wall
b=bricklayer(s)
Therefore T</span><span>∝1/b, and T=k/b. In this case k=8 so T=8/b.
When b=1, T=8.
When b=2, T=4.
We'd say that the time it would take for bricklayers to set up a wall would be inversely proportional to the amount of bricklayers available.</span>
Answer:
32 degrees fahrenheit
Step-by-step explanation:
The other endpoint (x,y)
(X+18)/2 = 16 then x=14
(Y-18)/2 = -16 then y=-14