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Finding the Fourth Proportional to 688.38, 949.95 and 389.62

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Solution

The fourth proportional to 688.38, 949.95 and 389.62 is: 537.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.38 : 949.95 = 389.62 : x
  2. Step 2: Convert to fraction form
    688.38/949.95 = 389.62/x
  3. Step 3: Cross multiply
    688.38x = 949.95 × 389.62
  4. Step 4: Simplify right side
    688.38x = 370,115.20
  5. Step 5: Solve for x
    x = 370,115.20/688.38
  6. Step 6: Final answer
    x = 537.67

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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.