Finding the Third Proportional to 390 and 623.50
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Solution
The third proportional to 390 and 623.50 is: 996.80
Step by Step Solution
- Step 1: Write the proportion equation
390 : 623.50 = 623.50 : x - Step 2: Convert to fraction form
390/623.50 = 623.50/x - Step 3: Cross multiply
390x = 623.50 × 623.50 - Step 4: Simplify right side
390x = 388,752.25 - Step 5: Solve for x
x = 388,752.25/390 - Step 6: Final answer
x = 996.80
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These problems maintain the same ratio (1.60) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.