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Finding the Fourth Proportional to 687.48, 948.72 and 407.64

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Solution

The fourth proportional to 687.48, 948.72 and 407.64 is: 562.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.48 : 948.72 = 407.64 : x
  2. Step 2: Convert to fraction form
    687.48/948.72 = 407.64/x
  3. Step 3: Cross multiply
    687.48x = 948.72 × 407.64
  4. Step 4: Simplify right side
    687.48x = 386,736.22
  5. Step 5: Solve for x
    x = 386,736.22/687.48
  6. Step 6: Final answer
    x = 562.54

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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.