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Finding the Fourth Proportional to 640.88, 961.52 and 256.12

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Solution

The fourth proportional to 640.88, 961.52 and 256.12 is: 384.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.88 : 961.52 = 256.12 : x
  2. Step 2: Convert to fraction form
    640.88/961.52 = 256.12/x
  3. Step 3: Cross multiply
    640.88x = 961.52 × 256.12
  4. Step 4: Simplify right side
    640.88x = 246,264.50
  5. Step 5: Solve for x
    x = 246,264.50/640.88
  6. Step 6: Final answer
    x = 384.26

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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.