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Finding the Fourth Proportional to 719.08, 992.28 and 420.40

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Solution

The fourth proportional to 719.08, 992.28 and 420.40 is: 580.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    719.08 : 992.28 = 420.40 : x
  2. Step 2: Convert to fraction form
    719.08/992.28 = 420.40/x
  3. Step 3: Cross multiply
    719.08x = 992.28 × 420.40
  4. Step 4: Simplify right side
    719.08x = 417,154.51
  5. Step 5: Solve for x
    x = 417,154.51/719.08
  6. Step 6: Final answer
    x = 580.12

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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.