Finding the Third Proportional to 720 and 1,380
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Solution
The third proportional to 720 and 1,380 is: 2,645
Step by Step Solution
- Step 1: Write the proportion equation
720 : 1,380 = 1,380 : x - Step 2: Convert to fraction form
720/1,380 = 1,380/x - Step 3: Cross multiply
720x = 1,380 × 1,380 - Step 4: Simplify right side
720x = 1,904,400 - Step 5: Solve for x
x = 1,904,400/720 - Step 6: Final answer
x = 2,645
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Why These Related Problems?
These problems maintain the same ratio (1.92) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.