Home / 1,278.90-1,918.98-457.20

Finding the Fourth Proportional to 1,278.90, 1,918.98 and 457.20

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Solution

The fourth proportional to 1,278.90, 1,918.98 and 457.20 is: 686.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.90 : 1,918.98 = 457.20 : x
  2. Step 2: Convert to fraction form
    1,278.90/1,918.98 = 457.20/x
  3. Step 3: Cross multiply
    1,278.90x = 1,918.98 × 457.20
  4. Step 4: Simplify right side
    1,278.90x = 877,357.66
  5. Step 5: Solve for x
    x = 877,357.66/1,278.90
  6. Step 6: Final answer
    x = 686.03

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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.