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Finding the Fourth Proportional to 1,315.09, 1,815.13 and 818.11

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Solution

The fourth proportional to 1,315.09, 1,815.13 and 818.11 is: 1,129.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,315.09 : 1,815.13 = 818.11 : x
  2. Step 2: Convert to fraction form
    1,315.09/1,815.13 = 818.11/x
  3. Step 3: Cross multiply
    1,315.09x = 1,815.13 × 818.11
  4. Step 4: Simplify right side
    1,315.09x = 1,484,966.93
  5. Step 5: Solve for x
    x = 1,484,966.93/1,315.09
  6. Step 6: Final answer
    x = 1,129.18

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1.5x scale

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.