Finding the Third Proportional to 390 and 486
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Solution
The third proportional to 390 and 486 is: 605.63
Step by Step Solution
- Step 1: Write the proportion equation
390 : 486 = 486 : x - Step 2: Convert to fraction form
390/486 = 486/x - Step 3: Cross multiply
390x = 486 × 486 - Step 4: Simplify right side
390x = 236,196 - Step 5: Solve for x
x = 236,196/390 - Step 6: Final answer
x = 605.63
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