Podemos adicionar string e int em javascript

string + number = concatenated string

number + number = the sum of both numbers

string - number = the difference between (coerced string) and the number

"" + 1 + 10 + 2 = (string) "1102"    
"1102" - 5      = (number)  1097
1097 + "8"      = (string) "10798"
zizi-engi