Home / 1,211.40-1,817.10-345.72

Finding the Fourth Proportional to 1,211.40, 1,817.10 and 345.72

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Solution

The fourth proportional to 1,211.40, 1,817.10 and 345.72 is: 518.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,211.40 : 1,817.10 = 345.72 : x
  2. Step 2: Convert to fraction form
    1,211.40/1,817.10 = 345.72/x
  3. Step 3: Cross multiply
    1,211.40x = 1,817.10 × 345.72
  4. Step 4: Simplify right side
    1,211.40x = 628,207.81
  5. Step 5: Solve for x
    x = 628,207.81/1,211.40
  6. Step 6: Final answer
    x = 518.58

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Double scale
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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.