Help, is this correct?

Suppose the first five terms of a sequence are 4, 5, 9, 27, 123. how could the next term in the sequence be generated?

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

What are the equivalent ratios for 24/2= /3= /5.5=108/ = /15