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Finding the Fourth Proportional to 619.79, 855.28 and 340

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Solution

The fourth proportional to 619.79, 855.28 and 340 is: 469.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.79 : 855.28 = 340 : x
  2. Step 2: Convert to fraction form
    619.79/855.28 = 340/x
  3. Step 3: Cross multiply
    619.79x = 855.28 × 340
  4. Step 4: Simplify right side
    619.79x = 290,795.20
  5. Step 5: Solve for x
    x = 290,795.20/619.79
  6. Step 6: Final answer
    x = 469.18

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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.