Home / 329.80-455.40-286.60

Finding the Fourth Proportional to 329.80, 455.40 and 286.60

Calculator

Solution

The fourth proportional to 329.80, 455.40 and 286.60 is: 395.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    329.80 : 455.40 = 286.60 : x
  2. Step 2: Convert to fraction form
    329.80/455.40 = 286.60/x
  3. Step 3: Cross multiply
    329.80x = 455.40 × 286.60
  4. Step 4: Simplify right side
    329.80x = 130,517.64
  5. Step 5: Solve for x
    x = 130,517.64/329.80
  6. Step 6: Final answer
    x = 395.75

Related Problems

Find fourth proportional to 164.90, 227.70 and 143.30
Half scale
Find fourth proportional to 659.60, 910.80 and 573.20
Double scale
Find fourth proportional to 330.80, 456.78 and 287.60
Similar ratio
Find fourth proportional to 494.70, 683.10 and 429.90
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.