Today eight friends went for lunch there total bill was $34.56, including tax. One of them ordered always soda and needed to pay only $1.94. The other seven friends or the same daily special. How much did each of the other friends need to pay?

How many liters of peroxide should be added to 12 liters of an 8% peroxide solution so that the resulting solution contains 16% peroxide?   original added new amount of peroxide 0.96 liters x 0.96 + x amount of solution 12 liters x 12 + x 0.18 liter 1.14 liters 1.92 liters 2.10 liters