The text book store sold a combined total of 326 history and chemistry textbooks in a week. The number of chemistry textbooks sold was 86 less than the number of history textbooks sold. How many textbooks of each type was sold?

The sentence

"The Number of Chem textbooks sold is 86 less than the number of History textbooks"

This seems to be the confusing part.

Now look at it this way...

'If CHM text is 86 less than History text... It also means that History Text is 86 More than CHM'

This expression can be written as

Let History Text be "H"

Let CHM text be "C"

C - 86 = H

or

C=H + 861

First line of this question is interpreted thus

H + C = 3262

From eqn 1... C=H+86

Substitute into Eqn 2

H + C=326

H + (H+86)=326

H+H=326-86

2H=240

H=240/2

H=120.

C=H+86

C=120+86

C=206.

This answer is correct... Why?

The key statement says .. The Number of CHM sold is 86 less than History...

Also interpreted as

The Number of CHM – 86 = History

206 - 86 =120.

Have a great day!!!

answer:

it is general formula that is used to write value to its excet position

a11 a12 a13

a21 a22 a23

it is the example of order 2 by 3 matrix in this

a11 means value occur in 1 st row 1st column

a12 means value occurs in 1st row 2nd column

a13 means value occur in 1st row and 3rd column

a21 means value occurs in 2nd row and 1st column

a22 means value occurs in 2nd row and in 2nd column

a23 means value occurs in 2nd row and in 3rd column

[2, 2.5)

(2.5, 3]

step-by-step explanation:

i think its these two not sure [2, 2.5)

(2.5, 3]