A health research institute collects information from 20 individuals on the number of years they have spent smoking cigarettes, and their age of death. The data is summarized below: ∑x=1257
∑y^2=836
∑x^2=98823
∑y=116
∑(xy)=8249

Find the correlation coefficient (r):

The correlation coefficient of the health research institute data measures the relationship between the age and the years of the smokers

The correlation coefficient is 0.53

The correlation coefficient (r) is calculated as:

Using the given parameters, we have:

Evaluate the exponents

Evaluate the products

Evaluate the differences

Evaluate the product

Evaluate the root

Evaluate the quotient

Hence, the correlation coefficient is 0.53

Read more about correlation coefficient at:

The answer is in the image 

The answer is in the image 

F=ma

where F=force

m=mass

a=acceleration

Here,

F=4300

a=3.3m/s2

m=F/a

    =4300/3.3

    =1303.03kg

F=ma

where F=force

m=mass

a=acceleration

Here,

F=4300

a=3.3m/s2

m=F/a

    =4300/3.3

    =1303.03kg

Approximately it is aqual to 1300kg

The answer is in the image 

The wood before starting =12 feet

Left wood=6 feet

Wood used till now=12-6=6 feet

Picture frame built till now= 6/(3/4)

=8 pieces

Therefore, till now 8 pieces have been made.

Salesperson will make 6% of 1800

=(6/100)*1800

=108

Salesperson will make $108 in $1800 sales

30% of 420 are first year students

first year students = (30/100 )*420

=126 students

Student who are not in first year = 420-126

=294 students