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Finding the Fourth Proportional to 666.79, 1,000.58 and 256.21

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Solution

The fourth proportional to 666.79, 1,000.58 and 256.21 is: 384.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.79 : 1,000.58 = 256.21 : x
  2. Step 2: Convert to fraction form
    666.79/1,000.58 = 256.21/x
  3. Step 3: Cross multiply
    666.79x = 1,000.58 × 256.21
  4. Step 4: Simplify right side
    666.79x = 256,358.60
  5. Step 5: Solve for x
    x = 256,358.60/666.79
  6. Step 6: Final answer
    x = 384.47

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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.