Answer:
<u>The</u><u> </u><u>requ</u><u>ired</u><u> </u><u>num</u><u>ber</u><u> is</u><u> </u><u>7</u><u>0</u><u>.</u>
Step-by-step explanation:
let the no. be 10y + x where x is unit digit and y is ten's digit.
given , sum of the digit is 7
x + y = 7 ...(1)
also , reversing the no. we get 10x + y ,where x is ten's digit and y is unit digit.
given reversed digit decreases the number by 63 .
so, 10y + x - ( 10x + y ) = 63
9y -9x = 63
( dividing both side by 9 )
y - x = 7 ....(2)
adding 1 and 2 [ refer attachment ]
so the required original number is
10y + x = 10×7+0 = 70
The calculation for circumference is 2πr or 2 × π (pi=3.14) × radius of a circle
Since the diameter of this circle is 7cm, and the radius is half of the diameter, 7 ÷ 2 = 3.5
So, 2×3.14(π)×3.5=21.98
Answer:
Step-by-step explanation:
This is permutation, since order matters. The formula for us is
₁₈P₅ = 
which simplifies to
₁₈P₅ = 
The factorial of 13 cancels out on the top and bottom leaving you with
₁₈P₅ = 18 × 17 × 16 × 15 × 14
which comes to 1,028,160 ways
Another way to look at it is: the first 5 people of 18 finish and the others you don't care about. Once the first place person is first, there are only 4 of the 18 left to finish in second place. Then there are only 3 left to finish in third place, etc. So if we use that reasoning, we don't even need to use the formula, we can just say
18 * 17 * 16 * 15 * 14 and those are the first 5 people of 18 to finish.
Answer:
The statement in the question is wrong. The series actually diverges.
Step-by-step explanation:
We compute
Therefore, by the series divergence test, the series 
diverges.
EDIT: To VectorFundament120, if 
is a sequence, both 
and 
are common notation for its limit. The former is not wrong but I have switched to the latter if that helps.
