Finding the Third Proportional to 396 and 840
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Solution
The third proportional to 396 and 840 is: 1,781.82
Step by Step Solution
- Step 1: Write the proportion equation
396 : 840 = 840 : x - Step 2: Convert to fraction form
396/840 = 840/x - Step 3: Cross multiply
396x = 840 × 840 - Step 4: Simplify right side
396x = 705,600 - Step 5: Solve for x
x = 705,600/396 - Step 6: Final answer
x = 1,781.82
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These problems maintain the same ratio (2.12) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.