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Finding the Fourth Proportional to 653.63, 980.71 and 393.79

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Solution

The fourth proportional to 653.63, 980.71 and 393.79 is: 590.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.63 : 980.71 = 393.79 : x
  2. Step 2: Convert to fraction form
    653.63/980.71 = 393.79/x
  3. Step 3: Cross multiply
    653.63x = 980.71 × 393.79
  4. Step 4: Simplify right side
    653.63x = 386,188.89
  5. Step 5: Solve for x
    x = 386,188.89/653.63
  6. Step 6: Final answer
    x = 590.84

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.