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Finding the Fourth Proportional to 1,428.90, 2,140.52 and 810.74

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Solution

The fourth proportional to 1,428.90, 2,140.52 and 810.74 is: 1,214.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,428.90 : 2,140.52 = 810.74 : x
  2. Step 2: Convert to fraction form
    1,428.90/2,140.52 = 810.74/x
  3. Step 3: Cross multiply
    1,428.90x = 2,140.52 × 810.74
  4. Step 4: Simplify right side
    1,428.90x = 1,735,405.18
  5. Step 5: Solve for x
    x = 1,735,405.18/1,428.90
  6. Step 6: Final answer
    x = 1,214.50

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1.5x scale

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.