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Finding the Fourth Proportional to 647.42, 970.86 and 257.36

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Solution

The fourth proportional to 647.42, 970.86 and 257.36 is: 385.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.42 : 970.86 = 257.36 : x
  2. Step 2: Convert to fraction form
    647.42/970.86 = 257.36/x
  3. Step 3: Cross multiply
    647.42x = 970.86 × 257.36
  4. Step 4: Simplify right side
    647.42x = 249,860.53
  5. Step 5: Solve for x
    x = 249,860.53/647.42
  6. Step 6: Final answer
    x = 385.93

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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.