Home / 1,281.09-1,921.62-459.42

Finding the Fourth Proportional to 1,281.09, 1,921.62 and 459.42

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Solution

The fourth proportional to 1,281.09, 1,921.62 and 459.42 is: 689.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,281.09 : 1,921.62 = 459.42 : x
  2. Step 2: Convert to fraction form
    1,281.09/1,921.62 = 459.42/x
  3. Step 3: Cross multiply
    1,281.09x = 1,921.62 × 459.42
  4. Step 4: Simplify right side
    1,281.09x = 882,830.66
  5. Step 5: Solve for x
    x = 882,830.66/1,281.09
  6. Step 6: Final answer
    x = 689.12

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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.