Some Precise Questions (Beginner)

Hello !

"A trader with a $10,000 account balance decides that the US Dollar (USD) is undervalued against the Euro (EUR). The current bid/ask price for EUR/USD is 1.2348/1.2350 – meaning a trader can buy 1 EUR for $1.2350 USD or sell 1 EUR for $1.2348 USD. The trader decides to sell EUR (buy dollars) by selling 1 standard lot. With leverage at 100:1 or 1%, initial margin deposit for this trade is $1,000, leaving the account balance at $9,000. As anticipated, the EUR/USD drops 48 pips to 1.2298/1.2300. To exit the position the trader would close 1 lot at 1.2300 In this scenario the trader has realized a profit of 48 pips or $480 US Dollars."

This is a Forex education from ForexMeta.com.
I have questions. Please point me where I am right or wrong on each item.
1. USD is undervalued means exchange rate currently is high and so exchange rate will go down soon. "Anticipated" means exchange rate will go down and it means from 1.2348/1.2350 to lower number/lower number(such as 1.2300/1.2345 here in this example 1.2298/1.2300)
2. It says 48 pips difference but 50 pips and I think it is a calculation mistake.
3. Why does the trader decied to sell EUR?
4. Sell Euro at 1.2348?
5. After EURUSD drops to 1.2298/1.2300(Does this mean exchange rate go down?) the trader sell Euro or buy Euro?
6. First sell Euro then buy Euro? Sell Euro at 1.2348 and buy Euro at 1.2300?
7. Where did 48 pips come from?
8. 1 pip is a $10. Where does it come from?

I'm posting it here because it has been hard to find answers !!! Thanks very much for your help !

Regards.

If you think the USD is undervalued (which I'm not saying), then that means the USD would show strength. So in the EURUSD, that would cause the EURUSD to go down. The GBPUSD, the GBPUSD would go down, but against something like the USDCHF or the USDJPY, they'd go up.

On the 48/50 pip thing, don't forget the spread. The ask was at 1.2350, the bid at 1.2348. When you short, you do so at the bid, meaning you'd sell at 1.2348. To close the position you have to buy back, so if the ask price then goes to 1.2300 and you close, that's a net of 48 pips.

The example they gave is bad on money management tho. W/o an SL they're risking 10% of their account. IMO they should be risking only $200. If their SL was, say, 50 pips, then that'd be $4 per pip (4 $10k lots) instead of $10 per pip. Your $$ per pip will depend on the lot size you trade.

Why did the trader decide to sell? Because he thought it was going down. Why'd he think it was going down? Who knows, it's a hypothetical situation.

5 (and 6). Indeed if a currency pair is said to "drop" it means the exchange rate goes lower, or down. At the moment of closing the position, it is equivalent to buying it back, that is, if he sold Euro at 1.2348, he is buying Euro back at 1.2300 thus making a profit on the transaction:
(1.2348-1.2300)*100000 = $480

8. 1 pip on Euro is 0,0001 (1/100th of a cent). 1 standard lot (the real total amount of the position he is transacting) is $100000.
100000*0,0001 = $10.

thank you very much ! You helped me a lot !!
Regards.