Home / 1,415.30-2,122.95-645.80

Finding the Fourth Proportional to 1,415.30, 2,122.95 and 645.80

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Solution

The fourth proportional to 1,415.30, 2,122.95 and 645.80 is: 968.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,415.30 : 2,122.95 = 645.80 : x
  2. Step 2: Convert to fraction form
    1,415.30/2,122.95 = 645.80/x
  3. Step 3: Cross multiply
    1,415.30x = 2,122.95 × 645.80
  4. Step 4: Simplify right side
    1,415.30x = 1,371,001.11
  5. Step 5: Solve for x
    x = 1,371,001.11/1,415.30
  6. Step 6: Final answer
    x = 968.70

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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.