If \(cosπx=x^2-x+ {5 \over 4}\), the value of \(x\) will be
If sinθ + sin2θ + sin3θ = 1, then cos6θ - 4cos4θ + 8cos2θ is
A dishonest grocer sells rice at a profit of 10% and uses weights which are 20% less than the marked weight. The total gain earned by him will be
Rekha and Sonali received Rs.2800 as wages for 20 days for the work they did together. Rekha’s efficiency in the work was three times that of the Sonali. What are the daily wages of Sonali?
Akhil rides first 12 km at a speed of 16 km/h and further 6 km at a speed of 20 km/h. Find his average speed (in km/h).