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Finding the Fourth Proportional to 618.90, 928.39 and 340.90

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Solution

The fourth proportional to 618.90, 928.39 and 340.90 is: 511.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.90 : 928.39 = 340.90 : x
  2. Step 2: Convert to fraction form
    618.90/928.39 = 340.90/x
  3. Step 3: Cross multiply
    618.90x = 928.39 × 340.90
  4. Step 4: Simplify right side
    618.90x = 316,488.15
  5. Step 5: Solve for x
    x = 316,488.15/618.90
  6. Step 6: Final answer
    x = 511.37

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1.5x scale

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.