(i made it 15 points but i think u get like 13? )how much of a spice that is 30% salt should be added to 175 ounces of a spice that is 65% salt in order to make a spice that is 50% salt?

131.25 ounces



Explanation:

We have two spices. Call them spice A and spice B

Spice A is 30% salt. We do not know how much of this spice to add, so we'll call it x. The x is a placeholder for a number
So on your paper you might write
x = amount of spice that is 30% salt (amount in ounces)
30% of x = 0.30*x is the amount of pure salt we have in spice A

Spice B is 65% salt. We have 175 ounces of this stuff. 
65% of 175 = 0.65*175 = 113.75 ounces are pure salt
So we have 0.30x+113.75 ounces of total pure salt from the two spices combined

The total mix is x+175 ounces. We want 50% of the total mix to be pure salt, so 0.50*(x+175) is the expression that represents this.

Set the expression 0.30x+113.75 and 0.50*(x+175) equal to each other. Solve for x
0.30x+113.75 = 0.50*(x+175)
0.30x+113.75 = 0.50*x+0.50*175
0.30x+113.75 = 0.50*x+87.5
0.50*x+87.5 = 0.30x+113.75
0.50*x-0.30x = 113.75-87.5
0.20x = 26.25
x = 26.25/0.20
x = 131.25

Exponential function