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Finding the Fourth Proportional to 687.79, 947.58 and 563.45

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Solution

The fourth proportional to 687.79, 947.58 and 563.45 is: 776.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.79 : 947.58 = 563.45 : x
  2. Step 2: Convert to fraction form
    687.79/947.58 = 563.45/x
  3. Step 3: Cross multiply
    687.79x = 947.58 × 563.45
  4. Step 4: Simplify right side
    687.79x = 533,913.95
  5. Step 5: Solve for x
    x = 533,913.95/687.79
  6. Step 6: Final answer
    x = 776.28

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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.