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Finding the Fourth Proportional to 647.19, 970.79 and 214.31

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Solution

The fourth proportional to 647.19, 970.79 and 214.31 is: 321.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.19 : 970.79 = 214.31 : x
  2. Step 2: Convert to fraction form
    647.19/970.79 = 214.31/x
  3. Step 3: Cross multiply
    647.19x = 970.79 × 214.31
  4. Step 4: Simplify right side
    647.19x = 208,051.36
  5. Step 5: Solve for x
    x = 208,051.36/647.19
  6. Step 6: Final answer
    x = 321.47

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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.