First part of the question:
Let x be the number of small boxes and y be the number of large boxes.
According to the first statement, a total of 24 boxes were shipped
=> x+y=24 ---- (Eq.1)
=> x = 24-y --- (Eq.2)
According to 2nd statement, Total weight was 1410 and we know the weight of one small box is 45 and large box is 75.
Therefore,
45x+75y=1410 --- (Eq.3)
Now, using the substitution method for solving the equation,
From equation 1,
Now putting Eq. 3 values,
Now putting value of y in Eq.2,
Therefore,
Number of small boxes shipped=x=13
Number of large boxes shipped=y=12
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Second part of question:
Define the variables that you use to write the system.
Ans:
x is used as a variable to show the number of small boxes.
y is used as a variable to show the number of large boxes.