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Finding the Fourth Proportional to 72.10, 108.10 and 64.30

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Solution

The fourth proportional to 72.10, 108.10 and 64.30 is: 96.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.10 : 108.10 = 64.30 : x
  2. Step 2: Convert to fraction form
    72.10/108.10 = 64.30/x
  3. Step 3: Cross multiply
    72.10x = 108.10 × 64.30
  4. Step 4: Simplify right side
    72.10x = 6,950.65
  5. Step 5: Solve for x
    x = 6,950.65/72.10
  6. Step 6: Final answer
    x = 96.40

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.