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Finding the Fourth Proportional to 655.62, 904.64 and 390.15

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Solution

The fourth proportional to 655.62, 904.64 and 390.15 is: 538.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    655.62 : 904.64 = 390.15 : x
  2. Step 2: Convert to fraction form
    655.62/904.64 = 390.15/x
  3. Step 3: Cross multiply
    655.62x = 904.64 × 390.15
  4. Step 4: Simplify right side
    655.62x = 352,943.35
  5. Step 5: Solve for x
    x = 352,943.35/655.62
  6. Step 6: Final answer
    x = 538.34

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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.