Finding the Third Proportional to 780 and 1,178
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Solution
The third proportional to 780 and 1,178 is: 1,779.08
Step by Step Solution
- Step 1: Write the proportion equation
780 : 1,178 = 1,178 : x - Step 2: Convert to fraction form
780/1,178 = 1,178/x - Step 3: Cross multiply
780x = 1,178 × 1,178 - Step 4: Simplify right side
780x = 1,387,684 - Step 5: Solve for x
x = 1,387,684/780 - Step 6: Final answer
x = 1,779.08
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These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.