Sort:  

correct,
1+5 = 6 * 3 = 18
2+10=12 * 3 = 36
3 + 15= 18 * 3 = 54
therefore
4 + 20 = 24 * 3 = 72

Coin Marketplace

STEEM 0.24
TRX 0.24
JST 0.039
BTC 103278.83
ETH 3265.94
SBD 5.82