Home / 643.08-964.40-210.12

Finding the Fourth Proportional to 643.08, 964.40 and 210.12

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Solution

The fourth proportional to 643.08, 964.40 and 210.12 is: 315.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.08 : 964.40 = 210.12 : x
  2. Step 2: Convert to fraction form
    643.08/964.40 = 210.12/x
  3. Step 3: Cross multiply
    643.08x = 964.40 × 210.12
  4. Step 4: Simplify right side
    643.08x = 202,639.73
  5. Step 5: Solve for x
    x = 202,639.73/643.08
  6. Step 6: Final answer
    x = 315.11

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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.