Answer:
13
Step-by-step explanation:
First set up your two equations:
x + y = 90
x = 2y - 30
Then substitute what x equals in the second equation into the first equation:
(2y -30) + y = 90
Now solve for y:
3y -30 = 90
3y = 120
y = 40
Then use y = 40 and substitute the value for y into one of your original equations and solve for x. I'll choose the first one, but either one will work.
x+ 40 = 90
x = 50
So your solution is x = 50 and y = 40
Answer:
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And using the probability mass function we got:
Step-by-step explanation:
Let X the random variable of interest, on this case we now that:
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
And we want to find the following probability:
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And using the probability mass function we got:
Answer:
or 0.6
Step-by-step explanation:
Answer:
40
Step-by-step explanation:
step 1: (-4)^2=16
step2: 12X2=24
step3: 16+24+40
Ps: when you do a math that involves both addition and multiplication,
we should do multiplication and then addition