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Finding the Fourth Proportional to 1,289.10, 1,779.72 and 847.76

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Solution

The fourth proportional to 1,289.10, 1,779.72 and 847.76 is: 1,170.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.10 : 1,779.72 = 847.76 : x
  2. Step 2: Convert to fraction form
    1,289.10/1,779.72 = 847.76/x
  3. Step 3: Cross multiply
    1,289.10x = 1,779.72 × 847.76
  4. Step 4: Simplify right side
    1,289.10x = 1,508,775.43
  5. Step 5: Solve for x
    x = 1,508,775.43/1,289.10
  6. Step 6: Final answer
    x = 1,170.41

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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.