Home / 780.32-1,170.48-324

Finding the Fourth Proportional to 780.32, 1,170.48 and 324

Calculator

Solution

The fourth proportional to 780.32, 1,170.48 and 324 is: 486

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.32 : 1,170.48 = 324 : x
  2. Step 2: Convert to fraction form
    780.32/1,170.48 = 324/x
  3. Step 3: Cross multiply
    780.32x = 1,170.48 × 324
  4. Step 4: Simplify right side
    780.32x = 379,235.52
  5. Step 5: Solve for x
    x = 379,235.52/780.32
  6. Step 6: Final answer
    x = 486

Related Problems

Find fourth proportional to 390.16, 585.24 and 162
Half scale
Find fourth proportional to 1,560.64, 2,340.96 and 648
Double scale
Find fourth proportional to 781.32, 1,171.98 and 325
Similar ratio
Find fourth proportional to 1,170.48, 1,755.72 and 486
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.