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Finding the Fourth Proportional to 620.65, 856.50 and 340.87

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Solution

The fourth proportional to 620.65, 856.50 and 340.87 is: 470.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.65 : 856.50 = 340.87 : x
  2. Step 2: Convert to fraction form
    620.65/856.50 = 340.87/x
  3. Step 3: Cross multiply
    620.65x = 856.50 × 340.87
  4. Step 4: Simplify right side
    620.65x = 291,953.45
  5. Step 5: Solve for x
    x = 291,953.45/620.65
  6. Step 6: Final answer
    x = 470.40

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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.