What quantity of 60 per cent acid solution must be mixed with a 25 per cent solution to produce 420 mL of a 50 per cent solution?

12 out of 30 people chose their favourite colour as blue caculate the angle you would use for blue on a pie chart

Can someone me with my math problem pls my teacher is on my back about this

Walter is to make cookies for a basketball tournament. he's made 15 cookies so far. his coach asked him to make at least 20 cookies but no more than 55. solve the inequality and interpret the solution. 20 ? x + 15 ? 55