Finding the Third Proportional to 321 and 690
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Solution
The third proportional to 321 and 690 is: 1,483.18
Step by Step Solution
- Step 1: Write the proportion equation
321 : 690 = 690 : x - Step 2: Convert to fraction form
321/690 = 690/x - Step 3: Cross multiply
321x = 690 × 690 - Step 4: Simplify right side
321x = 476,100 - Step 5: Solve for x
x = 476,100/321 - Step 6: Final answer
x = 1,483.18
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Why These Related Problems?
These problems maintain the same ratio (2.15) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.