Finding the Third Proportional to 312 and 438
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Solution
The third proportional to 312 and 438 is: 614.88
Step by Step Solution
- Step 1: Write the proportion equation
312 : 438 = 438 : x - Step 2: Convert to fraction form
312/438 = 438/x - Step 3: Cross multiply
312x = 438 × 438 - Step 4: Simplify right side
312x = 191,844 - Step 5: Solve for x
x = 191,844/312 - Step 6: Final answer
x = 614.88
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These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.