Q4. A large sphere of radius ‘R’ cm was converted into 64 small spheres of radius ‘r’ cm and then one small sphere is converted into 16 smaller cones of radius of ‘a’ cm. If height of cone is two times of its radius, then find R:a:r.
Q5. If three coins are tossed simultaneously, find the probability of getting minimum 2 head at a time.
Q6. The sum of area of a circle & area of a rectangle is equal to 2136 sq. cm. The diameter of the circle is 42 cm. What is the difference between the circumference of the circle & the perimeter of the rectangle, if the breath of the rectangle is 30 cm?
(a) 42 cm
(b) 22 cm
(c) 30 cm
(d) 11 cm
Q7. A solid is in the form of a cylinder with hemispherical ends. If the height of the solid is 26cm and diameter of cylindrical part is 14cm, then find the cost of covering the solid with metal sheet (Cost of metal sheet is Rs.15/cm²).
Q12. A sells man has 6 red and 5 black shirts. If two shirts are picked up randomly, then what is the probability of getting shirts of same color?
Q13. Find number of words that can be formed using all the letters of a English word ‘DHARMENDER’.
Q14. In how many ways 5 girls and 3 boys be arranged in a row all facing north such that no boy sit together?