Dylan and Rael went to buy mobile phones at a sale. The usual price of 1 mobile phone was $1300 each.

SALE
Buy 1 mobile phone at 5% discount
Buy 2 or more mobile phones at 20% discount each

1. Dylan bought 1 mobile phone. How much did he pay?
2. What is the maximum number of mobile phones Rael can buy if he has $5000?

(a)
Discounted price of 1 mobile phone in percent if only 1 was bought
= 100% - 5%
= 95%

100% of 1 mobile phone = 1300
1% of 1 mobile phone = 1300 ÷ 100 = 13
95% of 1 mobile phone = 95 x 13 = 1235 

Amount that Dylan paid for 1 mobile phone = $1235

(b)
Discounted price of 1 mobile phone in percent if more than 1 was bought
= 100% - 20%
= 80%

80% of 1 mobile phone = 80 x 13 = 1040

Amount that Rael paid for 1 mobile phone = $1040

Maximum number of mobile phones that Rael can buy if he has $5000
= 5000 ÷ 1040
= 4 r 840

Answer(s): (a) $1235; (b) 4