Home / 1,221.40-1,832.30-399.49

Finding the Fourth Proportional to 1,221.40, 1,832.30 and 399.49

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Solution

The fourth proportional to 1,221.40, 1,832.30 and 399.49 is: 599.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.40 : 1,832.30 = 399.49 : x
  2. Step 2: Convert to fraction form
    1,221.40/1,832.30 = 399.49/x
  3. Step 3: Cross multiply
    1,221.40x = 1,832.30 × 399.49
  4. Step 4: Simplify right side
    1,221.40x = 731,985.53
  5. Step 5: Solve for x
    x = 731,985.53/1,221.40
  6. Step 6: Final answer
    x = 599.30

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1.5x scale

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.