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Mom has $190$ coins in total and wants to give them to Sana as the pocket money. She gives Sana $30$ coins for the first month, and $40$ coins for each of the following months. How many months in total can Sana get the pocket money? 
Overseas Competition->Knowledge Point->Counting Modules
$190-30=160$  $40+40+40+40=160$  $4+1=5$ 