The histogram is especially useful in comparing mean and median values of a variable. We have that 5.5+6+7+10+7.5+8+9.5+9+8.5+8+7+7.5+6+6.5+5.5=111.5 Since there are 15 values, their mean is 111.5/15=7.43 which is very close to the mean. We also have that 7 onservations are lower than 7.4 while 8 are bigger than 7.4; hence, the diagram is rather balanced and not left-skewed. We cannot tell immediately which one is larger since the values are too close. Any such random process can usually be approximated to a greater or smaller degree by a normal curve; the more points, the better. The histogram shows this (it is kind of a discrete normal curve); all points except 4 will be in this interval of bars.
-7 times -8 is 56 and -40 divided by 10 is -4
The number of recycle bins that the city gives to citizens:
7204 : 2= 3602
The number of recycle bins is left:
7204 - 3602= 3602
The largest number of bins that can be given in each group:
3602 : 23 = 156 (residual: 14)
=> There are 14 bins left over.
Answer: He spends more time trading stickers by 15 minutes.
Step-by-step: 1 hour is 60 minutes. So 2 hours is 120 minutes. 120 minutes plus his 20 minutes is 140 minutes. Subtract it from his homework time and he spends 15 more minutes trading stickers.
If you are working with time or days, you can't put in a negative value because if you are doing an experiment, you can't go back in time to do that experiment to gather data. (Time for the most part considered to be an input value so that's why I used it as an example.)