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Finding the Fourth Proportional to 65.79, 90.64 and 57.03

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Solution

The fourth proportional to 65.79, 90.64 and 57.03 is: 78.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.79 : 90.64 = 57.03 : x
  2. Step 2: Convert to fraction form
    65.79/90.64 = 57.03/x
  3. Step 3: Cross multiply
    65.79x = 90.64 × 57.03
  4. Step 4: Simplify right side
    65.79x = 5,169.20
  5. Step 5: Solve for x
    x = 5,169.20/65.79
  6. Step 6: Final answer
    x = 78.57

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.