<span>We have 75 mL of 4% sugar solution.
We have to add a 30% sugar </span><span>solution to make a 50% </span><span>sugar solution.
75 * .04 + .30x = .50 * (75 +x)
3 + .30x = 37.5 +.50x
I can't get the equation to solve.
Did you type it correctly? For one thing, you have the percentages typed as .30 % and 4%. Are the decimal places in the correct positions?
Also, no matter how much 30% sugar solution you add, it will NEVER increase to 50%.
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There are 100 pennies in a dollar. We can divide 12000 pennies by 100 to find out how much they are worth in dollars.
12000/100 = $120