question: John decides to buy new phones for him, his 2 kids, and his wife.  Each phone after the first 2 is half price.  If the phone price is $600 how much did he pay for them all?
answer: He bought 1+2+1=<<1+2+1=4>>4 phones
  2 of the phones cost 600 so their cost is 2*600=$<<2*600=1200>>1200
  The other two phones cost 600/2=$<<600/2=300>>300
  So they cost 300*2=$<<300*2=600>>600
  So the total cost is 1200+600=$<<1200+600=1800>>1800
  #### 1800