A smartphone seller is offering a discount of 5% off for customers who buy at least 2 smartphones at once. Melinda, Zoe and Joel want to buy an iPhone X each. If an iPhone X costs $600, how much can they save by pooling their money together and buying three iPhones at once from this seller rather than buying individually?
Each iPhone X cost $600 so three iPhone Xs without the discount would cost 3*$600 = $<<3*600=1800>>1800
The discount is 5% and 5% of $1800 is (5/100)*$1800 = $<<5/100*1800=90>>90 which is what they get to save by buying collectively.
#### 90