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Finding the Fourth Proportional to 656.63, 906.15 and 407.80

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Solution

The fourth proportional to 656.63, 906.15 and 407.80 is: 562.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.63 : 906.15 = 407.80 : x
  2. Step 2: Convert to fraction form
    656.63/906.15 = 407.80/x
  3. Step 3: Cross multiply
    656.63x = 906.15 × 407.80
  4. Step 4: Simplify right side
    656.63x = 369,527.97
  5. Step 5: Solve for x
    x = 369,527.97/656.63
  6. Step 6: Final answer
    x = 562.76

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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.