Home / 1,287,806.40-1,931,709.60-811,915.20

Finding the Fourth Proportional to 1,287,806.40, 1,931,709.60 and 811,915.20

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Solution

The fourth proportional to 1,287,806.40, 1,931,709.60 and 811,915.20 is: 1,217,872.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287,806.40 : 1,931,709.60 = 811,915.20 : x
  2. Step 2: Convert to fraction form
    1,287,806.40/1,931,709.60 = 811,915.20/x
  3. Step 3: Cross multiply
    1,287,806.40x = 1,931,709.60 × 811,915.20
  4. Step 4: Simplify right side
    1,287,806.40x = 1,568,384,386,225.92
  5. Step 5: Solve for x
    x = 1,568,384,386,225.92/1,287,806.40
  6. Step 6: Final answer
    x = 1,217,872.80

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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.