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Finding the Fourth Proportional to 687.18, 949.23 and 654.78

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Solution

The fourth proportional to 687.18, 949.23 and 654.78 is: 904.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.18 : 949.23 = 654.78 : x
  2. Step 2: Convert to fraction form
    687.18/949.23 = 654.78/x
  3. Step 3: Cross multiply
    687.18x = 949.23 × 654.78
  4. Step 4: Simplify right side
    687.18x = 621,536.82
  5. Step 5: Solve for x
    x = 621,536.82/687.18
  6. Step 6: Final answer
    x = 904.47

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Double scale
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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.