Question

An internet download speed is 4.2 MB/S (constant). How long will it take to download a 30 GB file?

And with 900 KB/S?

Answer 1

(a)

(b)

Step-by-step explanation:

Given

Required

Download time

Solving (a): When Speed =4.2Mb/s

Speed is calculated as:

Make Time the subject:

Substitute values for File Size and Speed

Convert Gb to Mb

Convert to minutes

When converted, it is approximately 2 hours

Solving (a): When Speed =900Kb/s

Substitute values for File Size and Speed

Convert Gb to Kb

Convert to hours

Answer 2

(a)
`Time= 119.05 \ min`

(b)
`Time= 9.26\ hr`

Step-by-step explanation:

Given

`File = 30GB`

Required

Download time

Solving (a): When Speed =4.2Mb/s

Speed is calculated as:

`Speed = (File\ Size)/(Time)`

Make Time the subject:

`Time= (File\ Size)/(Speed )`

Substitute values for File Size and Speed

`Time= (30Gb)/(4.2Mb/s)`

Convert Gb to Mb

`Time= (30*1000Mb)/(4.2Mb/s)`

`Time= (30000s)/(4.2)`

Convert to minutes

`Time= (30000)/(4.2*60)\ min`

`Time= (30000)/(252)\ min`

`Time= 119.05 \ min`

When converted, it is approximately 2 hours

Solving (a): When Speed =900Kb/s

`Time= (File\ Size)/(Speed )`

Substitute values for File Size and Speed

`Time= (30Gb)/(900Kb/s)`

Convert Gb to Kb

`Time= (30*1000000Kb)/(900Kb/s)`

`Time= (30*1000000s)/(900)`

`Time= (1000000s)/(30)`

`Time= (100000)/(3)s`

Convert to hours

`Time= (100000)/(3*3600)hr`

`Time= (1000)/(3*36)hr`

`Time= (1000)/(108)hr`

`Time= 9.26\ hr`