Answer: 0.9961
Step-by-step explanation:
Given: Total choices to each question = 4
So, the probability that an answer is correct = 
Total questions = 20
i.e. n= 20
Let x be the binomial variable that represents the number of correct answers.
So, the probability that the student has at least 10 correct answers.
[By using cumulative binomial table]
Hence, the probability that the student has at least 10 correct answers = 0.9961
21, 28, and 35 are multiples of 7. So you can divide each number by 7 (in other words scaling the triangle down by a scale factor of 7).
It becomes 3,4,5, which is the base Pythagorean triple.
3^2 + 4^2 = 5^2
9 + 16 = 25
You can't deliver ANY oranges to Everett. The tax for the trip is 1,000 oranges,
and that's also the size of the full load. You only carry enough to pay the tax
along the way, and you arrive at Everett with an empty truck. The only way
you can deliver ANY oranges to Everett would be with a bigger truck, that
can carry more. (But then the tax might also be more for a bigger truck.)
=============================
Well now, wait just a minute. Don't go away. I don't know if this
is the greatest possible number, but I know how you can get 500
oranges all the way there. I have to warn you that this method
does involve considerable risk:
-- Load up with 1,000 oranges.
-- Drive half-way to Everett. It costs you 500 oranges,
so you have 500 left on the truck. UNLOAD the truck
right there, by the side of the road, and cover the 500
oranges with grass and leaves so no animals or people
will know that they are there.
-- Return to Orangeland with your empty truck. That trip
costs you no tax.
-- Load your truck with the remaining 1,000 oranges.
-- Drive halfway to Everett again. It costs you 500 oranges
in road tax, so you arrive at the halfway point with 500 oranges
still on your truck.
-- Stop at the halfway point. Search relentlessly for the 500 oranges
that you left there earlier. Clean them off when you finally find them,
and load them back on your truck. Your truck is now fully loaded again
with 1,000 oranges.
-- Drive the rest of the way to Everett. That half of the trip costs another
500 oranges in tax, and you arrive in Everett with 500 oranges.
I hope this helps you
this triangle is isosceles right triangle
base=height
Area=base×height /2
18=b×b/2
b^2=36
b=6
