Answer:
20×(5×(-16) = (20×5)×(-16)
Step-by-step explanation:
They both equal -1600
Answer:
-499,485.
Step-by-step explanation:
We can transform this to an arithmetic series by working it out in pairs:
6^2 - 7^2 = (6-7)(6+7) = -13
8^2 - 9^2 = (8-9)*8+9) = -17
10^2 - 11^2 = -1 * 21 = -21 and so on
The common difference is -4.
The number of terms in this series is (998 - 6) / 2 + 1
= 992/2 + 1 = 497.
Sum of n terms of an A.S:
= n/2 [2a1 + (n - 1)d
Here a1 = -13, n = 497, d = -4:
Sum = (497/2)[-26 - 4(497-1)]
= 497/2 * -2010
= -499,485.
Answer:
1 and 3 are biased
Step-by-step explanation:
A biased sample is ond where all individuals were not given equal likelihood of being selected.
Number 1;
Picking students from the cafeteria would lead to sampling bias because not every student from the school eats from the cafeteria. Those she selected can not be used to account for the whole school. Those that use the cafeteria are only a representation of the whole school and not the entire school.
For number 3:
Paul is interested in finding the mean number of cloth shoppers In a mall and is only collecting data from one clothing store without considering other stores in the mall.
Answer:
-27
Step-by-step explanation:
Um it is the third brainiest please
