Home / 1,187.20-1,780.08-456.40

Finding the Fourth Proportional to 1,187.20, 1,780.08 and 456.40

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Solution

The fourth proportional to 1,187.20, 1,780.08 and 456.40 is: 684.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,187.20 : 1,780.08 = 456.40 : x
  2. Step 2: Convert to fraction form
    1,187.20/1,780.08 = 456.40/x
  3. Step 3: Cross multiply
    1,187.20x = 1,780.08 × 456.40
  4. Step 4: Simplify right side
    1,187.20x = 812,428.51
  5. Step 5: Solve for x
    x = 812,428.51/1,187.20
  6. Step 6: Final answer
    x = 684.32

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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.