At a supermarket , monica paid 3.20 for 2 pounds of apples and 2 pounds of oranges, while sarah paid 4.40 for 2 pounds of apples and 4 pounds of oranges. at these rates, what is the cost , in dollars, for 3 pounds of oranges?

The cost , in dollars, for 3 pounds of oranges is 1.8

Solution:

Given that Monica paid 3.20 for 2 pounds of apples and 2 pounds of oranges

Sarah paid 4.40 for 2 pounds of apples and 4 pounds of oranges.

Let the cost of orange per pound = x  

Let the cost of apple per pound = y  

Therefore, we can frame an equation as follows for Monica and Sarah:

In Monica’s case:  

2x + 2y = 3.20  

Hence x + y = 1.6 eqn 1

In Sarah’s case:  

4x + 2y = 4.40  

Hence 2x + y = 2.2

y = 2.2 -2x – eqn 2

Substitute eqn 2 in eqn 1 we get,

x + 2.2 -2x = 1.6

-x = 1.6-2.2 = -0.6

x = 0.6

Substituting the value of “x” in eqn 2 we get the value of “y” as 1

Thus the cost of orange per pound is 0.6

Therefore, cost of 3 pounds of oranges = 3 × 0.6 = 1.8

11

step-by-step explanation:

32.50-7.50=25

225/25=11

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116