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Finding the Fourth Proportional to 65.20, 90.06 and 51.40

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Solution

The fourth proportional to 65.20, 90.06 and 51.40 is: 71.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.20 : 90.06 = 51.40 : x
  2. Step 2: Convert to fraction form
    65.20/90.06 = 51.40/x
  3. Step 3: Cross multiply
    65.20x = 90.06 × 51.40
  4. Step 4: Simplify right side
    65.20x = 4,629.08
  5. Step 5: Solve for x
    x = 4,629.08/65.20
  6. Step 6: Final answer
    x = 71.00

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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.