When mixing 50% and 10% solutions of the same substance, a 15% solution was obtained. How many times took more by weight of a 10% solution than a 50% solution?
let the mass of a 10% solution be n times greater, then
m is the mass of a 50% solution, and n * m is the mass of a 10% solution, then
0.5m + 0.1 * (n * m) = 0.15 * (m + n * m)
0.5 + 0.1n = 0.15 + 0.15n
0.05n = 0.35
n = 7
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.