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Finding the Fourth Proportional to 687.04, 947.28 and 479.68

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Solution

The fourth proportional to 687.04, 947.28 and 479.68 is: 661.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.04 : 947.28 = 479.68 : x
  2. Step 2: Convert to fraction form
    687.04/947.28 = 479.68/x
  3. Step 3: Cross multiply
    687.04x = 947.28 × 479.68
  4. Step 4: Simplify right side
    687.04x = 454,391.27
  5. Step 5: Solve for x
    x = 454,391.27/687.04
  6. Step 6: Final answer
    x = 661.38

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1.5x scale

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.