I need help with this also this is one step equations

Ametalworker has a metal alloy that is 30? % copper and another alloy that is 55? % copper. how many kilograms of each alloy should the metalworker combine to create 90 kg of a 50? % copper? alloy?

Drag the tiles to the table. the tiles can be used more than once. nd g(x) = 2x + 5 model a similar situation. find the values of f(x) and g(x) let's say that the functions f(x for the given values of x. fix)=5(4) * g(x) = 2x+5

Aswimming pool had 2.5 million liters of water in it. some water evaporated, and then the pool only had 22 million liters of water in it. what percent of the water evaporated?