Answer:
112
Step-by-step explanation:
cause if you calculated it it will be 112.2222 so the closest thing is 112
Answer:
1 is 13
2 is 13
3 is -7
4 is 7
Step-by-step explanation:
Answer:
Step-by-step explanation:
The formula for determining the sum of the first n terms of an arithmetic sequence is expressed as
Sn = n/2[2a + (n - 1)d]
Where
n represents the number of terms in the arithmetic sequence.
d represents the common difference of the terms in the arithmetic sequence.
a represents the first term of the arithmetic sequence.
If a = 5, the expression for the sum of the first 12 terms is
S12 = 12/2[2 × 5 + (12 - 1)d]
S12 = 6[10 + 11d]
S12 = 60 + 66d
Also, the expression for the sum of the first 3 terms is
S3 = 3/2[2 × 5 + (3 - 1)d]
S3 = 1.5[10 + 2d]
S3 = 15 + 3d
The sum of the first 12 terms is equal to ten times the sum of the first 3 terms. Therefore,
60 + 66d = 10(15 + 3d)
60 + 66d = 150 + 30d
66d + 30d = 150 - 60
36d = 90
d = 90/36
d = 2.5
For S20,
S20 = 20/2[2 × 5 + (20 - 1)2.5]
S20 = 10[10 + 47.5)
S20 = 10 × 57.5 = 575
Answer:
The value of x is 75
Step-by-step explanation:
First we need to find the other angle that doesn't have a number in it.
To find the degrees of the other angle we subtract 155 from 180.
180 - 155 = 25
Now we have to find the value of x. Add 80 and 25 together to get 105. A triangle is going to be 180 degrees. Subtract 105 from 180.
180 - 105 = 75
Now we will add 80, 25, and 75 to check our work.
80+25+75 = 180
