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Finding the Fourth Proportional to 1,214.08, 1,675.29 and 690

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Solution

The fourth proportional to 1,214.08, 1,675.29 and 690 is: 952.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,214.08 : 1,675.29 = 690 : x
  2. Step 2: Convert to fraction form
    1,214.08/1,675.29 = 690/x
  3. Step 3: Cross multiply
    1,214.08x = 1,675.29 × 690
  4. Step 4: Simplify right side
    1,214.08x = 1,155,950.10
  5. Step 5: Solve for x
    x = 1,155,950.10/1,214.08
  6. Step 6: Final answer
    x = 952.12

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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.