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Finding the Fourth Proportional to 651.90, 899.81 and 390.07

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Solution

The fourth proportional to 651.90, 899.81 and 390.07 is: 538.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.90 : 899.81 = 390.07 : x
  2. Step 2: Convert to fraction form
    651.90/899.81 = 390.07/x
  3. Step 3: Cross multiply
    651.90x = 899.81 × 390.07
  4. Step 4: Simplify right side
    651.90x = 350,988.89
  5. Step 5: Solve for x
    x = 350,988.89/651.90
  6. Step 6: Final answer
    x = 538.41

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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.