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Finding the Fourth Proportional to 420.83, 630.63 and 305.51

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Solution

The fourth proportional to 420.83, 630.63 and 305.51 is: 457.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.83 : 630.63 = 305.51 : x
  2. Step 2: Convert to fraction form
    420.83/630.63 = 305.51/x
  3. Step 3: Cross multiply
    420.83x = 630.63 × 305.51
  4. Step 4: Simplify right side
    420.83x = 192,663.77
  5. Step 5: Solve for x
    x = 192,663.77/420.83
  6. Step 6: Final answer
    x = 457.82

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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.