Answer:The mean for the howler monkeys is 17 and the MAD is 0.8571.
The mean for the spider monkeys is 14 and the MAD is 1.1429.
The means-to-MAD ratio is 2.6249.
Step-by-step explanation:
To find the mean of the howler monkeys, add all of the data values and divide by 7:
(15+16+17+17+17+17+18+19)/7 = 119/7 = 17
To find the MAD, subtract each data point from the mean; take the absolute deviation; then average these together:
(|15-17|+|16-17|+|17-17|+|17-17|+|17-17|+|17-17|+|18-17|+|19-17|)/7
=(2+1+0+0+0+0+1+2)/7=6/7 = 0.8571
Repeating these processes for the spider monkeys:
Mean:(12+13+13+14+14+14+16+16)/7 = 98/7 = 14
MAD:
(|12-14|+|13-14|+|13-14|+|14-14|+|14-14|+|14-14|+|16-14|+|16-14|)/7
=(2+1+1+0+0+0+2+2)/7 = 8/7 = 1.1429