Home / 1,430.60-2,145.90-390.61

Finding the Fourth Proportional to 1,430.60, 2,145.90 and 390.61

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Solution

The fourth proportional to 1,430.60, 2,145.90 and 390.61 is: 585.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,430.60 : 2,145.90 = 390.61 : x
  2. Step 2: Convert to fraction form
    1,430.60/2,145.90 = 390.61/x
  3. Step 3: Cross multiply
    1,430.60x = 2,145.90 × 390.61
  4. Step 4: Simplify right side
    1,430.60x = 838,199.27
  5. Step 5: Solve for x
    x = 838,199.27/1,430.60
  6. Step 6: Final answer
    x = 585.91

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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.