WebToolArcFormula and interpretation
For ratio a:b and total T, shares are T·a/(a+b) and T·b/(a+b).
All ratio parts should use the same unit and the ratio-part sum must be nonzero.
Worked check
Dividing 120 in the ratio 2:3 gives 48 and 72 because the ratio has 5 total parts: 120 × 2/5 = 48 and 120 × 3/5 = 72. The two shares should add back to the original total.
Rule: For ratio a:b and total T, shares are T·a/(a+b) and T·b/(a+b). All ratio parts should use the same unit and the ratio-part sum must be nonzero. For a final check, estimate the expected size of the answer before copying it, keep units consistent, and round only the displayed result rather than intermediate values. Re-enter one simple case by hand when possible; a result with the wrong sign or order of magnitude usually points to an input or reference-base mistake.