Answer:
Number of high quality version downloads = 880
Step-by-step explanation:
Let,
x be the number of standard version songs downloaded
y be the number of high quality version songs downloaded
According to given statement,
x+y=1600 Eqn 1
2.8x+4.1y=5624 Eqn 2
Multiplying Eqn 1 by 2.8 to eliminate x
2.8(x+y=1600)
2.8x+2.8y=4480 Eqn 3
Subtracting Eqn 3 from Eqn 2
(2.8x+4.1y)-(2.8x+2.8y)=5624-4480
2.8x+4.1y-2.8x-2.8y=1144
1.3y=1144
Dividing both sides by 1.3
Hence,
Number of high quality version downloads = 880
12598 rounded to the nearest thousands is 1260
These array of numbers shown above are called matrices. These are rectangular arrays of number that are arranged in columns and rows. It is mostly useful in solving a system of linear equations. For example, you have these equations
x+3y=5
2x+y=1
x+y=10
In matrix form that would be
where the first column are the coefficients of x, the second column the coefficients of y and the third column is the constants, When you multiple matrices, just multiply the same number on the same column number and the same row number. For this problem, the solution is