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Finding the Fourth Proportional to 688.30, 949.51 and 408.40

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Solution

The fourth proportional to 688.30, 949.51 and 408.40 is: 563.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.30 : 949.51 = 408.40 : x
  2. Step 2: Convert to fraction form
    688.30/949.51 = 408.40/x
  3. Step 3: Cross multiply
    688.30x = 949.51 × 408.40
  4. Step 4: Simplify right side
    688.30x = 387,779.88
  5. Step 5: Solve for x
    x = 387,779.88/688.30
  6. Step 6: Final answer
    x = 563.39

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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.