Answer:
5040
Step-by-step explanation:
The given series is :
24 + 48 + 72 + 96 +...+ 480
The first term, a= 24
Common difference, d = 24
The last term, 
Let there are n terms in the AP.
So,

There are 20 terms in the series. The sum of 20 terms is :

So, the sum of the given arithmetic series is equal to 5040.
Answer:
499/999
Step-by-step explanation:
The decimal number written is:
0.499...
Such that these 3 decimals are repeated as:
0.499499499...
Let's define this number as k
k = 0.499...
Let's multiply this number by 1000 (the same number of zeros as important decimals after the decimal point)
we get:
1000*k = (1000)*(0.499...) = 499.499...
Now we can subtract the original number k, so we get:
1000*k - k = 499.499... - 0.499...
In this way, we remove the part after the decimal point:
1000*k - k = 499.499... - 0.499...
(1000 - 1)*k = 499
999*k = 499
Now we can divide both sides by 999
(999*k)/999 = 499/999
k = 499/999
The fraction notation of our number is 499/999 (and this is the simplest form)
X=55 Explanation: the square is a right angle symbol and that means the angle is 90 degrees so just subtract 35 from the 90 to get x