Home / 1,281.25-1,921.88-459.76

Finding the Fourth Proportional to 1,281.25, 1,921.88 and 459.76

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Solution

The fourth proportional to 1,281.25, 1,921.88 and 459.76 is: 689.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,281.25 : 1,921.88 = 459.76 : x
  2. Step 2: Convert to fraction form
    1,281.25/1,921.88 = 459.76/x
  3. Step 3: Cross multiply
    1,281.25x = 1,921.88 × 459.76
  4. Step 4: Simplify right side
    1,281.25x = 883,596.45
  5. Step 5: Solve for x
    x = 883,596.45/1,281.25
  6. Step 6: Final answer
    x = 689.64

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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.