Home / 1,398.08-1,929.28-777.12

Finding the Fourth Proportional to 1,398.08, 1,929.28 and 777.12

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Solution

The fourth proportional to 1,398.08, 1,929.28 and 777.12 is: 1,072.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,398.08 : 1,929.28 = 777.12 : x
  2. Step 2: Convert to fraction form
    1,398.08/1,929.28 = 777.12/x
  3. Step 3: Cross multiply
    1,398.08x = 1,929.28 × 777.12
  4. Step 4: Simplify right side
    1,398.08x = 1,499,282.07
  5. Step 5: Solve for x
    x = 1,499,282.07/1,398.08
  6. Step 6: Final answer
    x = 1,072.39

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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.