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Finding the Fourth Proportional to 651.39, 976.01 and 420

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Solution

The fourth proportional to 651.39, 976.01 and 420 is: 629.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.39 : 976.01 = 420 : x
  2. Step 2: Convert to fraction form
    651.39/976.01 = 420/x
  3. Step 3: Cross multiply
    651.39x = 976.01 × 420
  4. Step 4: Simplify right side
    651.39x = 409,922.10
  5. Step 5: Solve for x
    x = 409,922.10/651.39
  6. Step 6: Final answer
    x = 629.30

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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.