For sake of convenience, reverse the series, then it would be:
21,19,17.....7
a=21, d = -2,
s(4) = 4/2 (21+15)
s(4)=2(36)
s(4) = 72
Let n represent the number.
1/3n = n - 12
Number one would be 13 because you have to add the x to both sides which will leave you with 2x=26 then you have to divide by 2 and you will get x=13. Number two is 7 7/8 because you have to add the 1/3x to the other 1/3x to get 2/3x= 5 1/4 so then you divide both sides by 2/3 and to divide a fraction you do keep change flip so it would be 21/4 times 3/2 which would be 63/8 which simplifys to 7 7/8.
Answer:
Step-by-step explanation:
no
Answer:
Step-by-step explanation:
This is how we do it in college, I hope I can be of some help.
First, you multiple 9.6 miles with 5 minutes. Then, you divide your answer with 0.4 miles. Next, you cancel the two mile units because of division and then be left with 120 minutes.
9.6 miles x <u> 5 minutes </u> = <u> 48 miles x minute </u> = 120 minutes
0.4 miles 0.4 miles