The number of Golden Delicious apple bought by Mary is 9.
Algebraic expressions are the combination of terms related together by arithmetic operations like addition, subtraction, and division.
Given:
Price of Delicious Apples = $ 0.75
Price of Golden Delicious Apples = $ 1.25
Total Number of Apples = 22
Total Price of Apples = $ 21.00
In the equation, x is for Delicious apples and y is for Golden delicious apples.
[tex]\begin {aligned}21 &= 0.75 x + 1.25 y .....(1)\\22 &= x + y .....(2)\\\\\end{aligned}[/tex]
[tex]\begin {aligned}\rm Putting\; the \;value\; of\; y\; in\; Equation\;(1):\\21 &= 0.75 x + 1.25 (22 - x)\\21 &= 0.75 x + 27.5 - 1.25 x\\-6.5 &= -0.5 x\\x &= 13\\\\\end{aligned}[/tex]
[tex]\begin {aligned}\rm Putting\; the \;value\; of\; x\; in\; Equation\;(2):\\y &=22 - x \\y &= 22 -13\\y&= 9\end{aligned}[/tex]
Thus, Mary bought 9 Golden Apples and 13 Delicious Apples.
Learn more about arithmetic operations here:
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