Three postal workers can sort a stack of mail in 15 minutes, 15 minutes, and 30 minutes, respectively. Find how long it takes them to sort the mail if all three work together. min

10 minutes

Step-by-step explanation:

x·1/20 + x·1/25 + x·1/100 = 1

Multiply each term by 100 to clear the equation of all fractions

100x/20 + 100x/25 + 100x/100 = 100

5x + 4x + 1x = 100

10x = 100

x = 10

The answer is 10 minutes

asnwer is (g o h o f)(x) = 2x - 6/x + 7

step-by-step explanation:

given,

f(x) = x - 3/x

g(x) = x + 3

h(x) = 2x + 1

we need to find : (g o h o f)(x)

we can write (g o h o f)(x) = g[ h{ f(x) } ]

so first we find h{f(x)}

h{f(x)} = f(x) + 3 = (x - 3/x) + 3

h{f(x)} = x - 3/x + 3

now we find g[ h{ f(x) } ].

g[ h{ f(x) } ] = g(x - 3/x + 3)       {plug h{f(x)} = x - 3/x + 3 in g[h{f(x)}] }

g(x - 3/x + 3) = 2 (x - 3/x + 3) + 1

                    = 2x - 6/x + 6 + 1

                    = 2x - 6/x + 7

hence we get (g o h o f)(x) = 2x - 6/x + 7