How much is 30% of 500¥?

i like the idea that one can buy app packs yet i find it utterly strange not to say bold that Grinasys Corp. as well as Apple (who offers the app) uses "fishy statements” to pull customers over the table. For instance this product… the running app is 200¥ the fitness app 300¥ (on 50% sale today)… buy both for 30% off the price which is 400¥. According to my school the price should be 350¥… another example? Same company different offer; buy the running app bundle (4 apps separately bought for 1700¥) by enjoying (according to the description) more than 50% off the normal price for… 900¥. Really? Who is going to give me my money back? Grinasys or Apple?

Shinsō about Weight Loss RUNNING PRO, v2.0