Answer:

Step-by-step explanation:
We know that for principal amount P , time period T and rate of interest
, simple interest is given by
.
Here ,

To find : simple interest rate i.e., 
On putting values of
in formula , we get 

Now we need to round off the answer to the nearest tenth .
So, simple interest rate is % =
=
Answer: 0.84
Step-by-step explanation:
let p be the population proportion of adults who smoked a cigarette in the past week.
As per given , we have

Sample size : n= 1491
The sample proportion of adults smoked a cigarette= 
The test statistic for proportion is given by :-

Substitute all the values , we get

Hence, the value of the test statistic = 0.84
-3(2r+7)=3
distribute -3
-6r-21=3
add 21 to both sides, this causes the 21 on the left to cancel itself out.
-6r=24
divide each side by -6, this causes the -6 on the left side to cancel itself out.
r=-4