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Finding the Fourth Proportional to 643.18, 970.53 and 620.30

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Solution

The fourth proportional to 643.18, 970.53 and 620.30 is: 936.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.18 : 970.53 = 620.30 : x
  2. Step 2: Convert to fraction form
    643.18/970.53 = 620.30/x
  3. Step 3: Cross multiply
    643.18x = 970.53 × 620.30
  4. Step 4: Simplify right side
    643.18x = 602,019.76
  5. Step 5: Solve for x
    x = 602,019.76/643.18
  6. Step 6: Final answer
    x = 936.01

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.