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Finding the Fourth Proportional to 655.68, 904.69 and 390.07

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Solution

The fourth proportional to 655.68, 904.69 and 390.07 is: 538.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    655.68 : 904.69 = 390.07 : x
  2. Step 2: Convert to fraction form
    655.68/904.69 = 390.07/x
  3. Step 3: Cross multiply
    655.68x = 904.69 × 390.07
  4. Step 4: Simplify right side
    655.68x = 352,892.43
  5. Step 5: Solve for x
    x = 352,892.43/655.68
  6. Step 6: Final answer
    x = 538.21

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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.