The mean age of the frequency distribution for the ages of the residents of a town is 43 years.
Step-by-step explanation:
We are given with the following frequency distribution below;
Answer:

Step-by-step explanation:
Please see the attached pictures for the full solution.
X= width
length= 3x-7
Area: (x)(3x-7)=40
= 3x^2-7x=40
= 3x^2-7x-40=0
Factorise the equation: (3x+8)(x-5)=0
x=-8/3 (reject because width cannot be negative) or x=5
so width is 5cm and length is 3(5)-7= 8cm !
3 1/8 = 25/8
25 and 8 have no common factors, so 25/8 is in simplest form.
You multiply the whole number by the denominator and then add the numerator and get 344/100 then simplify and then you get 86/25 then now its a improper fractions so turn it into a mixed number and its 3 11/25