abacus; soroban; calculation (esp. of profit and loss); reckoning
to count on the abacus; to calculate cost-benefit; to calculate profitability; to be guided by self-interest
counting on the abacus; cost-benefit calculation; profit calculation
the three Rs; reading, writing and arithmetic
mercenary; calculative; greedy; commercial-minded; venal
the figures add up; the calculation comes out right; to be profitable; to pay
electronic calculator combined with a soroban