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Finding the Fourth Proportional to 714.72, 986.55 and 420.07

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Solution

The fourth proportional to 714.72, 986.55 and 420.07 is: 579.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    714.72 : 986.55 = 420.07 : x
  2. Step 2: Convert to fraction form
    714.72/986.55 = 420.07/x
  3. Step 3: Cross multiply
    714.72x = 986.55 × 420.07
  4. Step 4: Simplify right side
    714.72x = 414,420.06
  5. Step 5: Solve for x
    x = 414,420.06/714.72
  6. Step 6: Final answer
    x = 579.84

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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.