A scientist mixes water (containing no salt) with a solution that contains 35% salt. She wants to obtain 175 ounces of a mixture that is 20% salt. How many ounces of water and how many ounces of the 35% salt solution should she use?

Answer: There is 100 ounces of 35% salt solution and 100 ounces of water.Step-by-step explanation:Since we have given that Percent of salt in a solution = 35%Percent of salt in a mixture = 20%Number of ounces of a mixture = 175 ouncesWe need to find the number of ounces of water and salt as well as .We would use "Mixture and Allegation":       Salt                       Water       35%                           0%                        20%---------------------------------------------------------------20% - 0%          :                35% - 20%    20%              :                     15%    4                    :                      3 So, Ratio of salt and water in the mixture is 4 : 3.So, Number of ounces of salt in the mixture is given  by[tex]\dfrac{4}{7}\times 175\\\\=100\ ounces[/tex]Number of ounces of water in the mixture is given by[tex]\dfrac{3}{7}\times 175\\\\=75\ ounces[/tex]Hence, there is 100 ounces of 35% salt solution and 100 ounces of water.