Home / 900-1,241.64-638.34

Finding the Fourth Proportional to 900, 1,241.64 and 638.34

Calculator

Solution

The fourth proportional to 900, 1,241.64 and 638.34 is: 880.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    900 : 1,241.64 = 638.34 : x
  2. Step 2: Convert to fraction form
    900/1,241.64 = 638.34/x
  3. Step 3: Cross multiply
    900x = 1,241.64 × 638.34
  4. Step 4: Simplify right side
    900x = 792,588.48
  5. Step 5: Solve for x
    x = 792,588.48/900
  6. Step 6: Final answer
    x = 880.65

Related Problems

Find fourth proportional to 450, 620.82 and 319.17
Half scale
Find fourth proportional to 1,800, 2,483.28 and 1,276.68
Double scale
Find fourth proportional to 901, 1,243.02 and 639.34
Similar ratio
Find fourth proportional to 1,350, 1,862.46 and 957.51
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.