Home / 210.20-315.08-80.18

Finding the Fourth Proportional to 210.20, 315.08 and 80.18

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Solution

The fourth proportional to 210.20, 315.08 and 80.18 is: 120.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.20 : 315.08 = 80.18 : x
  2. Step 2: Convert to fraction form
    210.20/315.08 = 80.18/x
  3. Step 3: Cross multiply
    210.20x = 315.08 × 80.18
  4. Step 4: Simplify right side
    210.20x = 25,263.11
  5. Step 5: Solve for x
    x = 25,263.11/210.20
  6. Step 6: Final answer
    x = 120.19

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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.