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Finding the Fourth Proportional to 652.39, 900.30 and 390.40

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Solution

The fourth proportional to 652.39, 900.30 and 390.40 is: 538.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    652.39 : 900.30 = 390.40 : x
  2. Step 2: Convert to fraction form
    652.39/900.30 = 390.40/x
  3. Step 3: Cross multiply
    652.39x = 900.30 × 390.40
  4. Step 4: Simplify right side
    652.39x = 351,477.12
  5. Step 5: Solve for x
    x = 351,477.12/652.39
  6. Step 6: Final answer
    x = 538.75

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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.