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Finding the Fourth Proportional to 1,314.40, 1,970.80 and 620.12

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Solution

The fourth proportional to 1,314.40, 1,970.80 and 620.12 is: 929.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,314.40 : 1,970.80 = 620.12 : x
  2. Step 2: Convert to fraction form
    1,314.40/1,970.80 = 620.12/x
  3. Step 3: Cross multiply
    1,314.40x = 1,970.80 × 620.12
  4. Step 4: Simplify right side
    1,314.40x = 1,222,132.50
  5. Step 5: Solve for x
    x = 1,222,132.50/1,314.40
  6. Step 6: Final answer
    x = 929.80

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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.