Step-by-step explanation:
the positive integer numbers that are divisible by 7 are an arithmetic sequence by always adding 7 :
a1 = 7
a2 = a1 + 7 = 7+7 = 14
a3 = a2 + 7 = a1 + 7 + 7 = 7 + 2×7 = 21
...
an = a1 + (n-1)×7 = 7 + (n-1)×7 = n×7
the sum of an arithmetic sequence is
n/2 × (2a1 + (n - 1)×d)
with a1 being the first term (in our case 7).
d being the common difference from term to term (in our case 7).
how many terms (what is n) do we need to add ?
we need to find n, where the sequence reaches 200.
200 = n×7
n = 200/7 = 28.57142857...
so, with n = 29 we would get a number higher than 200.
so, n=28 gives us the last number divisible by 7 that is smaller than 200 (28×7 = 196).
the sum of all positive integers below 200 that are divisible by 7 is then
28/2 × (2×7 + 27×7) = 14 × 29×7 = 2,842
Answer:
Step-by-step explanation:I can’t see the opitons but what you would do is subtract 59.50 and 30.Then for the remain number every dollar is 4 people.
8 students out of 27
the total of students is 27 out of the 27 students 19 dont play and instrument and a sport
Answer:
Step-by-step explanation: Need to work out your scale factor which is 1.5.
8 * 1.5 = 12
CE = 12
12 * 9 = 108/2 = 59 that is the area of triangle ACE
8 * 6 = 48/2 = 24 that is the area of triangle BCD
ACE - BCD = ABDE
59 - 24 = 35cm^2
Answer:
Step-by-step explanation:
The graph shows the profile of your parabolic listening device,