Answered

Last year, there were 480 blue shirts and green shirts in the school.
This year, there are 498 blue shirts and green shirts. This includes a 2%
decrease in the number of blue shirts and a 10% increase in the number
of green shirts. How many blue shirts and green shirts were there in the
school last year?



Answer :

Answer:230

Step-by-step explanation:

Let x be the number of blue shirts last year and y be the number of green shirts last year

2From the given information, we can set up two equations:

x + y = 480 (equation 1)

0​.98x + 1.1y = 498 (equation 2)

3Solve the system of equations using substitution or elimination method

4Let's solve using elimination method. Multiply equation 1 by 1.1 to make the coefficients of y the same:

1​.1x + 1.1y = 528 (equation 3)

0​.98x + 1.1y = 498 (equation 2)

5Subtract equation 2 from equation 3 to eliminate y:

1​.1x - 0.98x = 528 - 498

0​.12x = 30

6Divide both sides of the equation by 0.12 to solve for x:

x = 30 / 0.12

x = 250

7Substitute the value of x into equation 1 to solve for y:

250 + y = 480

y = 480 - 250

y = 230