Answer: 15
Step-by-step explanation:
(r+1)th term of
is given by:-

For
, n= 6

![=\ \dfrac{6!}{4!2!}a^4b^2\ \ \ [^nC_r=\dfrac{n!}{r!(n-r)!}]\\\\=\dfrac{6\times5\times4!}{4!\times2}a^4b^2\\\\=3\times5a^4b^2\\\\ =15a^4b^2](https://tex.z-dn.net/?f=%3D%5C%20%5Cdfrac%7B6%21%7D%7B4%212%21%7Da%5E4b%5E2%5C%20%5C%20%5C%20%5B%5EnC_r%3D%5Cdfrac%7Bn%21%7D%7Br%21%28n-r%29%21%7D%5D%5C%5C%5C%5C%3D%5Cdfrac%7B6%5Ctimes5%5Ctimes4%21%7D%7B4%21%5Ctimes2%7Da%5E4b%5E2%5C%5C%5C%5C%3D3%5Ctimes5a%5E4b%5E2%5C%5C%5C%5C%20%3D15a%5E4b%5E2)
Hence, the coefficient of the third term in the binomial expansion of
is 15.
- two consecutive integers

<u>-4 and -3</u>
Answer:
60
Step-by-step explanation:
Set up a ratio problem
15/25 = 36/x
15x = 900
x = 60
<h3>
Answer: 360</h3>
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Explanation:
We have 3 even values (2,4, and 6) so this is the number of choices we have for the units digit. Recall that a number is even if the units digit is 0,2,4,6 or 8.
Once we have the units digit selected, we have 6-1 = 5 choices for the first slot, 6-2 = 4 choices for the second slot, and so on until we get down to 6-5 = 1 choice for the fifth slot
We could write it out like this
- slot one = 5 choices
- slot two = 4 choices
- slot three = 3 choices
- slot four = 2 choices
- slot five = 1 choice
- slot six = units digit = 3 choices
Multiply those values out: 5*4*3*2*1*3 = 360
There are 360 different even numbers possible.
Answer:
He should have to spell at least 36 of these words correctly.
Step-by-step explanation:
40 words.
He must spell at least 90% of those words correctly.
At least how many words should he have to spell correctly to get the prize?
90% of 40. So
0.9*40 = 4*9 = 36
He should have to spell at least 36 of these words correctly.