Finding the Fourth Proportional to 207.99, 312.12 and 86.34
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Solution
The fourth proportional to 207.99, 312.12 and 86.34 is: 129.57
Step by Step Solution
- Step 1: Write the proportion equation
207.99 : 312.12 = 86.34 : x - Step 2: Convert to fraction form
207.99/312.12 = 86.34/x - Step 3: Cross multiply
207.99x = 312.12 × 86.34 - Step 4: Simplify right side
207.99x = 26,948.44 - Step 5: Solve for x
x = 26,948.44/207.99 - Step 6: Final answer
x = 129.57
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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.