Ineed to solve these proplem , i should find the value of the happy face and sad face i need

The sad face means - 7

Just comment if you would like me to show work!!

7 + 6 = 13
7 x 6 = 42 
7 - 6 =1 
sad face = 7 

Hope it helps!

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post