Home / 643.11-964.58-210.21

Finding the Fourth Proportional to 643.11, 964.58 and 210.21

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Solution

The fourth proportional to 643.11, 964.58 and 210.21 is: 315.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.11 : 964.58 = 210.21 : x
  2. Step 2: Convert to fraction form
    643.11/964.58 = 210.21/x
  3. Step 3: Cross multiply
    643.11x = 964.58 × 210.21
  4. Step 4: Simplify right side
    643.11x = 202,763.31
  5. Step 5: Solve for x
    x = 202,763.31/643.11
  6. Step 6: Final answer
    x = 315.29

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1.5x scale

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.