Answer:
100
Step-by-step explanation:
85 +80+100+85+x(the unknown),/the number of numbers ie 5
350+x/5=90
350+x=90 * 5
350+x=450
x=450-350
x=100
Answer:
The sum of the first 650 terms of the given arithmetic sequence is 2,322,775
Step-by-step explanation:
The first term here is 4
while the nth term would be ai = a(i-1) + 11
Kindly note that i and 1 are subscript of a
Mathematically, the sum of n terms of an arithmetic sequence can be calculated using the formula
Sn = n/2[2a + (n-1)d)
Here, our n is 650, a is 4, d is the difference between two successive terms which is 11.
Plugging these values, we have
Sn = (650/2) (2(4) + (650-1)11)
Sn = 325(8 + 7,139)
Sn = 325(7,147)
Sn = 2,322,775
Answer:
B
Step-by-step explanation:
It is a very simple question to answer.
Obviously first we can calculate his weekly earnings and then multiply them by 4 to calculate his total earnings over the course of 4 year period.
So as he makes 6.2$ an hour. He will make 6.2 * 30 = 186 $ a week as that is the number of hours he works in a week.
Now we can multiply this by 4 to calculate his over all earnings. So 186 * 4 = 744.