How many ways can a team of 4 engineers be selected from a group of 7 engineers

a) 28
b) 35
c) 5,040
d) 840

There are 35 ways a team of 4 engineers can be selected from a group of 7 engineers ⇒ b

Step-by-step explanation:

Combinations are a way to calculate the total outcomes of an event where order of the outcomes does not matter.

To calculate combinations, we will use the formula , where

The order is not important in this problem, so we can use the  combination

∵ The group has 7 engineers

∴ n = 7

∵ The team has 4 engineers

∴ r = 4

∵  

∴  

∴  

∵ 7! = 7 × 6 × 5 × 4 × 3 × 2 × 1

∵ 4! = 4 × 3 × 2 × 1

∵ 3! = 3 × 2 × 1

∴ =

∴  = 35

There are 35 ways a team of 4 engineers can be selected from a group of 7 engineers

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have