Question 631789
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Hi,
A chemist needs 90 milliliters of a 42% solution but has only 38% and 47% solutions available.
 Set Up on ALL mixture problems is to have the same amount of the <u>key ingredient</u> on both sides of the EQ
Let x represent the amoount of 47% solution
  {{{.47x + .38(90-x) = .42*90}}}   | Solve for x, multiplying EQ thru by 100 first, if you like