He should order 10 sandwiches of 6 foot long so, as to make sure that everyone will eat 2 pieces.
We need to convert between the units in order to ensure the accuracy and to prevent measurement misinterpretation. For example, we do not measure the pencil's length in kilometres. In this situation, one must convert from kilometres (km) to centimetres (cm) (cm). In most cases, multiplicative conversion factors are used to convert one unit to another of the same quantity. Let's see how to change the length and mass units.
1 Feet = 12 Inches
So, 6 Foot = 72 inches
The Length of sandwich- piece is 4 inch
So, when we convert 6 foot long sandwich into 4 inch,
Then we get number of piece is = 72/4 = 18
From 6 foot long sandwich we get 18 pieces of 4 inch long sub.
Now, Total people who will attend picnic is 40
and each people will eat 2 pieces.
It means total number of piece required = 2 (90) = 180
Mr. eaton required 180 pieces of sandwiches.
Number of sandwiches = 180 / 1.8 = 10
He should order 10 sandwiches of 6 foot long.
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