Finding the Fourth Proportional to 420.99, 631.68 and 258.99
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Solution
The fourth proportional to 420.99, 631.68 and 258.99 is: 388.60
Step by Step Solution
- Step 1: Write the proportion equation
420.99 : 631.68 = 258.99 : x - Step 2: Convert to fraction form
420.99/631.68 = 258.99/x - Step 3: Cross multiply
420.99x = 631.68 × 258.99 - Step 4: Simplify right side
420.99x = 163,598.80 - Step 5: Solve for x
x = 163,598.80/420.99 - Step 6: Final answer
x = 388.60
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.