一條簡單數

let x be the number components
let y be the original efficiency in components/min

time required to complete task originally is,
x / y

increasing efficiency by 1/5 yields (1 1/5)y = (6/5)y
the improved time will be
x / (6/5)y = (5/6)(x/y)

the time is reduced by,
x/y - (5/6)(x/y)
= (1/6)(x/y)
which equals 60min, therefore,
(1/6)(x/y) = 60
x = 360y

with 120 components and original efficiency of y, time taken is
120 / y

increasing efficiency by 1/4 yields (1 1/4)y = (5/4)y, time taken is
120 / (5/4)y
= 96/y

time taken is reduced by
120/y - 96/y
= 24/y
which equals 40min
24/y = 40

y = 24 / 40 = 3/5 components/min

x = 360y = 360 * (3/5) = 216 components

首先- let x be 一共零件
1. x(1/5)=60mins (即1小時)
2. 120(1/4)=40 mins
交叉相乖: 60．120．1/4 = 40．1/5．x
1800=8x
x=225
一共225件零件