how do I do this?

thank you that helps alot 

Let the number =N

2 1/5N =5 13/15

11/5N =88/15 divide both sides by 11/5

N =88/15 / 11/5

N =88/15 X 5/11

N =440 / 165

N =2 2/3

5 + 13/15 =   88/15

2 + 1/5  =  11/5

Let n be the number

"of" means "multiply"   and " what" means "equal"     .......so....

88/15 * n   =   11/5       multiply both sides by 15/88

[15/88] * [88/15] n  =  [15/88] * [11/5]

n  = [15/88] * [11/5 ]  =  [15/5] * [ 11/88]  =  3/1 * 1/8  =   3/8

;)))))))))))))))))))))))))))))))))))