How to use "businesslike" in a sentence

Hundreds of gamblers - pretty young women, sweet-faced grandmothers, men in jeans and decoratively stitched Western shirts, retirement-age men in expensive but tacky leisure outfits, a few guys in three-piece suits, salesmen, doctors, mechanics, secretaries, Americans from all of the Western states, junketeers from the East Coast, Japanese tourists, a few Arab men - sat at the semielliptical blackjack tables, pushing money and chips forward, sometimes taking back their winnings, eagerly grabbing the cards that were dealt from the five-deck shoes, each reacting in one of several predictable ways: Some players squealed with delight; some grumbled; others smiled ruefully and shook their heads; some teased the dealers, pleading half seriously for better cards; and still others were silent, polite, attentive, and businesslike, as though they thought they were engaged in some reasonable form of investment planning