Home / 1,420.35-2,130.33-380.40

Finding the Fourth Proportional to 1,420.35, 2,130.33 and 380.40

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Solution

The fourth proportional to 1,420.35, 2,130.33 and 380.40 is: 570.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,420.35 : 2,130.33 = 380.40 : x
  2. Step 2: Convert to fraction form
    1,420.35/2,130.33 = 380.40/x
  3. Step 3: Cross multiply
    1,420.35x = 2,130.33 × 380.40
  4. Step 4: Simplify right side
    1,420.35x = 810,377.53
  5. Step 5: Solve for x
    x = 810,377.53/1,420.35
  6. Step 6: Final answer
    x = 570.55

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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.