adada

Half of 84 got stolen, Half of 42 was lost under the vat and through the drain
⅓  + ⅙ = 3/6 = ½ (3x2 = 6, 1x2 = 2 = 2/6, 2/6 + ⅙ = 3/6 = ½ )
½ of 42 is 21, and ⅓ was locked in a safe and 14 was taken home.
⅓ of 21 is 7, and 7 + 14 = 21.
21 x 2 = 42... Too easy.