Finding the Fourth Proportional to 312.11, 430.68 and 289.77
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Solution
The fourth proportional to 312.11, 430.68 and 289.77 is: 399.85
Step by Step Solution
- Step 1: Write the proportion equation
312.11 : 430.68 = 289.77 : x - Step 2: Convert to fraction form
312.11/430.68 = 289.77/x - Step 3: Cross multiply
312.11x = 430.68 × 289.77 - Step 4: Simplify right side
312.11x = 124,798.14 - Step 5: Solve for x
x = 124,798.14/312.11 - Step 6: Final answer
x = 399.85
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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.