Gabe went ot lunch with his best friend the bill costs 16.40 dollers before trax and tip he paid a 9 persent tax and left a 20 persent tip howm much did gabe spend

Step-by-step explanation:

Gabe went out for lunch with his best friend the bill costs $16.40

This amount was before tax and the tip that he wanted to give.

He paid a 9 percent tax on the bill. The amount of the 9 percent tax is 9/100 * 16.40 = 0.09 * 16.40 = $1.476

He left a 20 percent tip. This means that amount left as tip is 20/100 * 16.40 = 0.2*16.40 = $3.28

The amount that Gabe paid would be the sum of the bill, the tip and the amount paid on tax. It becomes

16.40 + 1.476 + 3.28 = $21.156

Answer:21.45