Tushen murabba'in lamba mara kyau a (an nuna kamar √a) shine lambar b fiye da sifili, murabba'in (ko a wasu kalmomi ikon na biyu) wanda yake daidai da aIe
Umurnai don amfani: shigar da magana mai tsattsauran ra'ayi (wannan shine lambar a), sannan danna maballin "Lissafi". A sakamakon haka, za a ƙididdige tushen murabba'in ƙayyadaddun ƙimar.