x=5
14x5= 70
70-21=49
this is how I got the answer
Complete question is;
How many 10 - digit numbers are there, such that the sum of the digits is divisible by 2?
Answer:
There are 4500000000 ten digit numbers whose sum is divisible by 2.
Step-by-step explanation:
Since we are dealing with 10 digit numbers, the first 10 digit number whose sum is divisible by 2 is; 1000000001.
While the last 10 digit number whose sum is divisible by 2 is 9999999999.
Now,to find how many 10 digit numbers whose sum are divisible by 2, we will simply divide the difference of both numbers by 2 and then add 1 to the answer. This is because subtracting the minimum from the maximum gives us the number of 10 digit numbers we have. Then dividing by 2 gives the number of ten digit numbers with sum divisible by 2 in between. Then adding 1 to the result to cover the number not included gives;
((9999999999 - 1000000001)/2) + 1 = 4500000000
Answer:
7.5 pounds.
Step-by-step explanation:
the answer is 7.5 ponds because if each slider has 2 oz. then we can find the total number of oz. needed by multiplying by 60. This gets 120 oz that Scarlett needs in total. Since there are 16oz in a pound we divide 120 by 16 to find the number of pounds needed.
Imagine, at the first day you have only one penny. Then tomorrow you have 2 pennies, next day you have 4 (2x2), next day you have 8 (4x2), next day you have 16 (8x2).... and so forth.
It looks like geometric sequence isn't it? (the ratio between the number of pennies that you have from the 2nd day and the 1st day is 2)
So, by using geometric sequence theorem we can total those pennies until day-27
S (total pennies at day-27) = (1)(2^27-1) / 2-1 = 2^26 pennies
So, you have 2^26 pennies.. a big number of pennies huh?=))
{The formula is: S = a( r^n-1) / r-1
Where:
a= the number of pennies that you've got at the 1st day
n= number of days you spent to collect those pennies)
r= the ratio of the number of pennies}
A is the correct answer I hope that helps :)
