Home / 1,421.75-2,130.93-928.40

Finding the Fourth Proportional to 1,421.75, 2,130.93 and 928.40

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Solution

The fourth proportional to 1,421.75, 2,130.93 and 928.40 is: 1,391.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,421.75 : 2,130.93 = 928.40 : x
  2. Step 2: Convert to fraction form
    1,421.75/2,130.93 = 928.40/x
  3. Step 3: Cross multiply
    1,421.75x = 2,130.93 × 928.40
  4. Step 4: Simplify right side
    1,421.75x = 1,978,350.05
  5. Step 5: Solve for x
    x = 1,978,350.05/1,421.75
  6. Step 6: Final answer
    x = 1,391.49

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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.