Vincent and Xavier went to buy mobile phones at a sale. The usual price of 1 mobile phone was $1400 each.

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

1. Vincent bought 1 mobile phone. How much did he pay?
2. What is the maximum number of mobile phones Xavier can buy if he has $8000?

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

100% of 1 mobile phone = 1400
1% of 1 mobile phone = 1400 ÷ 100 = 14
95% of 1 mobile phone = 95 x 14 = 1330 

Amount that Vincent paid for 1 mobile phone = $1330

(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 14 = 1120

Amount that Xavier paid for 1 mobile phone = $1120

Maximum number of mobile phones that Xavier can buy if he has $8000
= 8000 ÷ 1120
= 7 r 160

Answer(s): (a) $1330; (b) 7