Finding the Third Proportional to 215 and 390
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Solution
The third proportional to 215 and 390 is: 707.44
Step by Step Solution
- Step 1: Write the proportion equation
215 : 390 = 390 : x - Step 2: Convert to fraction form
215/390 = 390/x - Step 3: Cross multiply
215x = 390 × 390 - Step 4: Simplify right side
215x = 152,100 - Step 5: Solve for x
x = 152,100/215 - Step 6: Final answer
x = 707.44
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These problems maintain the same ratio (1.81) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.