Home / 912-1,256.88-842.40

Finding the Fourth Proportional to 912, 1,256.88 and 842.40

Calculator

Solution

The fourth proportional to 912, 1,256.88 and 842.40 is: 1,160.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    912 : 1,256.88 = 842.40 : x
  2. Step 2: Convert to fraction form
    912/1,256.88 = 842.40/x
  3. Step 3: Cross multiply
    912x = 1,256.88 × 842.40
  4. Step 4: Simplify right side
    912x = 1,058,795.71
  5. Step 5: Solve for x
    x = 1,058,795.71/912
  6. Step 6: Final answer
    x = 1,160.96

Related Problems

Find fourth proportional to 456, 628.44 and 421.20
Half scale
Find fourth proportional to 1,824, 2,513.76 and 1,684.80
Double scale
Find fourth proportional to 913, 1,258.26 and 843.40
Similar ratio
Find fourth proportional to 1,368, 1,885.32 and 1,263.60
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.