Solve 15.99+4.89+7.89+2.79+5.49+3.89+3.89+9.49+6.79+10.99+12.40=

$$15.99+4.89+7.89+2.79+5.49+3.89+3.89+9.49+6.79+10.99+12.40=$$

Evaluate

$$84.5$$

Solution Steps

Add 15.99 and 4.89 to get 20.88.

$$20.88+7.89+2.79+5.49+3.89+3.89+9.49+6.79+10.99+12.4$$

Add 20.88 and 7.89 to get 28.77.

$$28.77+2.79+5.49+3.89+3.89+9.49+6.79+10.99+12.4$$

Add 28.77 and 2.79 to get 31.56.

$$31.56+5.49+3.89+3.89+9.49+6.79+10.99+12.4$$

Add 31.56 and 5.49 to get 37.05.

$$37.05+3.89+3.89+9.49+6.79+10.99+12.4$$

Add 37.05 and 3.89 to get 40.94.

$$40.94+3.89+9.49+6.79+10.99+12.4$$

Add 40.94 and 3.89 to get 44.83.

$$44.83+9.49+6.79+10.99+12.4$$

Add 44.83 and 9.49 to get 54.32.

$$54.32+6.79+10.99+12.4$$

Add 54.32 and 6.79 to get 61.11.

$$61.11+10.99+12.4$$

Add 61.11 and 10.99 to get 72.1.

$$72.1+12.4$$

Add 72.1 and 12.4 to get 84.5.

$$84.5$$

Factor

$$\frac{13 ^ {2}}{2} = 84\frac{1}{2} = 84.5$$