+1911 I have $4$ different mathematics textbooks and $3$ different psychology textbooks. In how many ways can I place the $7$ textbooks on a bookshelf, in a row, all the mathematics textbooks are together?
+37146 There is 4 P 4 ways to arange the block of 4 math books ....and 4 ways to place this block int groupof 7
4 P4 * 4 = 24 * 4 = 96 ways to arrange and place the math books
then there are 4 P 3 ways to arrange the remaining Psych books = 24 ways
24 x 96 = 2304 ways to arrange the books .
