Home / 1,208.08-1,812.40-428.04

Finding the Fourth Proportional to 1,208.08, 1,812.40 and 428.04

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Solution

The fourth proportional to 1,208.08, 1,812.40 and 428.04 is: 642.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,208.08 : 1,812.40 = 428.04 : x
  2. Step 2: Convert to fraction form
    1,208.08/1,812.40 = 428.04/x
  3. Step 3: Cross multiply
    1,208.08x = 1,812.40 × 428.04
  4. Step 4: Simplify right side
    1,208.08x = 775,779.70
  5. Step 5: Solve for x
    x = 775,779.70/1,208.08
  6. Step 6: Final answer
    x = 642.16

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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.