Answer:
the 13th one is 115
Step-by-step explanation:
Step-by-step explanation:

X+4=7
-4 -4
x=3
First subtract 4 from 4 and 7
Then keep the equal sign and x=3
Answer:
<em>When 60 beats are heard, Tom hits 15 snare drums, Sam hits 6 kettle drums, and Matt hits 5 bass drums.</em>
Step-by-step explanation:
The Least Common Multiple ( LCM )
The LCM of two integers a,b is the smallest positive integer that is evenly divisible by both a and b.
For example:
LCM(20,8)=40
LCM(35,18)=630
Since Tom, Sam, and Matt are counting drum beats at their own frequency, we must find the least common multiple of all their beats frequency.
Find the LCM of 4,10,12. Follow this procedure:
List prime factorization of all the numbers:
4 = 2*2
10 = 2*5
12 = 2*2*3
Multiply all the factors the greatest times they occur:
LCM=2*2*3*5=60
Thus, when 60 beats are heard, Tom hits 15 snare drums, Sam hits 6 kettle drums, and Matt hits 5 bass drums.
The numbers given in the problem above are part of an arithmetic sequence with first and sixth terms equal to -21 and -36, respectively. Firstly, calculate for the common difference (d).
d = (-36 - -21) / (6 - 1) = -3
The arithmetic mean is calculated by adding -3 to the term prior to it.
a2 = -21 + -3 = -24 a3 = -24 + -3 = -27
a4 = -27 + -3 = -30 a5 = -30 + -3 = -33
Thus the four arithmetic means are -24, -27, -30, and -33.