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Finding the Fourth Proportional to 687.63, 949.14 and 513.21

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Solution

The fourth proportional to 687.63, 949.14 and 513.21 is: 708.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.63 : 949.14 = 513.21 : x
  2. Step 2: Convert to fraction form
    687.63/949.14 = 513.21/x
  3. Step 3: Cross multiply
    687.63x = 949.14 × 513.21
  4. Step 4: Simplify right side
    687.63x = 487,108.14
  5. Step 5: Solve for x
    x = 487,108.14/687.63
  6. Step 6: Final answer
    x = 708.39

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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.