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Finding the Fourth Proportional to 647.21, 970.27 and 256.96

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Solution

The fourth proportional to 647.21, 970.27 and 256.96 is: 385.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.21 : 970.27 = 256.96 : x
  2. Step 2: Convert to fraction form
    647.21/970.27 = 256.96/x
  3. Step 3: Cross multiply
    647.21x = 970.27 × 256.96
  4. Step 4: Simplify right side
    647.21x = 249,319.29
  5. Step 5: Solve for x
    x = 249,319.29/647.21
  6. Step 6: Final answer
    x = 385.22

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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.