1/4 * 1/3 * 1/2 * 1/1 = 1/24 chance that all 4 letters are placed in the correct envelopes.
With the first envelope, there are 4 choices of letters, so the probability of picking the correct letter is 1/4.
With the second envelope, there are 3 remaining letters, so the probability of picking the correct letter is 1/3.
The same logic follows the the third and final letter.
Answer: -ab - 11a^2 - 3b + 3a
Step-by-step explanation:
i think this is what you're wanting? if not just comment what you need and i'll retry it!
Answer: Choice D
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Explanation:
The formula for the surface area of a cylinder is
We then replace r with 10 and h with 25. Keep in mind that the diameter is 20 mm, so the radius is half that at 10 mm.
So that's how we get to
If all 3 angles of a Triangle MUST equal 180°, then we know that we use the equation (for this triangle) to find the angle measurements as (180-90)/2 which means we are dividing 90/2 which is 45° for each angle. But these angles are different measures, so we have to guess upon this and say that YOUR ANSWER IS D
