Finding the Third Proportional to 720 and 1,320
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Solution
The third proportional to 720 and 1,320 is: 2,420
Step by Step Solution
- Step 1: Write the proportion equation
720 : 1,320 = 1,320 : x - Step 2: Convert to fraction form
720/1,320 = 1,320/x - Step 3: Cross multiply
720x = 1,320 × 1,320 - Step 4: Simplify right side
720x = 1,742,400 - Step 5: Solve for x
x = 1,742,400/720 - Step 6: Final answer
x = 2,420
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Why These Related Problems?
These problems maintain the same ratio (1.83) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.