How does 12345678 equal 101?

How does 12345678 equal 101?


1+2-3-4+5*(6+7+8)=101



What is 12345678 * 12345678@_@


152,428,110,957,684



12345678 is equal to 90. How can we calculate it only by addition


1+2+3+4+5+67+8=90