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Finding the Fourth Proportional to 666.55, 999.64 and 255.57

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Solution

The fourth proportional to 666.55, 999.64 and 255.57 is: 383.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.55 : 999.64 = 255.57 : x
  2. Step 2: Convert to fraction form
    666.55/999.64 = 255.57/x
  3. Step 3: Cross multiply
    666.55x = 999.64 × 255.57
  4. Step 4: Simplify right side
    666.55x = 255,477.99
  5. Step 5: Solve for x
    x = 255,477.99/666.55
  6. Step 6: Final answer
    x = 383.28

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.