Finding the Fourth Proportional to 660.32, 990.48 and 290
Calculator
Solution
The fourth proportional to 660.32, 990.48 and 290 is: 435
Step by Step Solution
- Step 1: Write the proportion equation
660.32 : 990.48 = 290 : x - Step 2: Convert to fraction form
660.32/990.48 = 290/x - Step 3: Cross multiply
660.32x = 990.48 × 290 - Step 4: Simplify right side
660.32x = 287,239.20 - Step 5: Solve for x
x = 287,239.20/660.32 - Step 6: Final answer
x = 435
Related Problems
Find fourth proportional to 330.16, 495.24 and 145
Half scale
Find fourth proportional to 1,320.64, 1,980.96 and 580
Double scale
Find fourth proportional to 661.32, 991.98 and 291
Similar ratio
Find fourth proportional to 990.48, 1,485.72 and 435
1.5x scale
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.