Let the cost of a chicken be x and the cost of a duck, y, then
50x + 30y = 550 . . . (1)
44x + 36y = 532 . . . (2)
(1) x 6 ⇒ 300x + 180y = 3,300 . . . (3)
(2) x 5 ⇒ 220x + 180y = 2,660 . . . (4)
(3) - (4) ⇒ 80x = 640
⇒ x = 640 / 80 = 8
From (1): 50(8) + 30y = 550
⇒ 30y = 550 - 400 = 150
⇒ y = 150 / 30 = 5
Therefore, the price of a chicken is $8 and the price of a duck is $5.
238 students are enrolled in the 7th grade class this year
<u>Solution: </u>
Given that
Percentage decrease in number of students enrolled in 7th grade = 15%
Number of students enrolled last year = 280
Need to determine number of students enrolled in 7th grade this year.
Lets assume number of students enrolled this year = x
<em>Percentage decrease in enrollment </em>= (Number of student enrolled last year – Number of students enrolled this year) whole divided by number of students enrolled last year multiplied by 100

Hence number of students enrolled this year = 238.
Answer:
Two real world situations are shown below.
Step-by-step explanation:
Initial population of a certain bacteria is 1 thousand and the population doubles in each hour. So, population of bacteria (in thousands) after x hours is
A person invests 1 lakh rupees in shares and the amount is twice at the end of each year. So, total amount (in lakhs) after x years is
15x10=150
Subtract 5x5=25 small square cut out
150 -25= 125 sq ft
D
Answer:
the minimum length of the first piece is 4 feet