Home / 1,720.18-2,580.25-421.65

Finding the Fourth Proportional to 1,720.18, 2,580.25 and 421.65

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Solution

The fourth proportional to 1,720.18, 2,580.25 and 421.65 is: 632.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,720.18 : 2,580.25 = 421.65 : x
  2. Step 2: Convert to fraction form
    1,720.18/2,580.25 = 421.65/x
  3. Step 3: Cross multiply
    1,720.18x = 2,580.25 × 421.65
  4. Step 4: Simplify right side
    1,720.18x = 1,087,960.30
  5. Step 5: Solve for x
    x = 1,087,960.30/1,720.18
  6. Step 6: Final answer
    x = 632.47

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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.