Question 3:- A restaurant sells three sizes of drinks: small for $1.20, medium for $1.30 and large for $1.80. Each person at a table of ten ordered one drink, for a total cost of $14.90, before sales tax. How many people ordered a large drink ?
Solution:- Let number of small sizes drink = s
Number of medium sizes drinks = m
and Number of large size drink = l
According to the question
1.2 s + 1.3 m + 1.8 l = 14.90 . . . (i)
And
s + m + l = 10
Multiply by 1.2 in this equation
1.2 s + 1.2 m + 1.2 l = 12 . . .(ii)
Substracting equation (i) to equation (ii)
We get,
0.1 m + 0.6 l = 2.9
Assume that the no of small and large size drink between 0 to 10 that satisfy this equation
Let l = 4 then
0.1 m + 0.6(4) = 2.9
⇒ 0.1 m + 2.4 = 2.9
⇒ 0.1 m = 2.9 – 2.4
⇒ 0.1 m = 0.5
⇒ m = 5
Thus the number of large size drink = 5
Question 2:- The length of a rectangle is three times its width. A new rectangle is created by decreasing the length of the original rectangle by 9 feet and increasing its width by 4 feet. The area of the new rectangle is the same as the area of the original rectangle. What is the perimeter of the new rectanle ?
Solution:- See full solution
Question 1:- A streaming video service offers its customers two plans. The first plan has a $ 24 registration fee, a fixed monthly rate of $5 and a charge of $0.75 for each video download. The second plan has a $15 registration fee, a fixed monthly rate of $3 and a charge of $1.50 for each vedio download. For how many download would the two plans cost the same for a year of service ?
Solution:- See full solution