Home / 21,985-30,338.40-12,909.13

Finding the Fourth Proportional to 21,985, 30,338.40 and 12,909.13

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Solution

The fourth proportional to 21,985, 30,338.40 and 12,909.13 is: 17,814.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,985 : 30,338.40 = 12,909.13 : x
  2. Step 2: Convert to fraction form
    21,985/30,338.40 = 12,909.13/x
  3. Step 3: Cross multiply
    21,985x = 30,338.40 × 12,909.13
  4. Step 4: Simplify right side
    21,985x = 391,642,349.59
  5. Step 5: Solve for x
    x = 391,642,349.59/21,985
  6. Step 6: Final answer
    x = 17,814.07

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.