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Finding the Fourth Proportional to 651.98, 899.42 and 390

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Solution

The fourth proportional to 651.98, 899.42 and 390 is: 538.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.98 : 899.42 = 390 : x
  2. Step 2: Convert to fraction form
    651.98/899.42 = 390/x
  3. Step 3: Cross multiply
    651.98x = 899.42 × 390
  4. Step 4: Simplify right side
    651.98x = 350,773.80
  5. Step 5: Solve for x
    x = 350,773.80/651.98
  6. Step 6: Final answer
    x = 538.01

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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.