For the following questions answer them individually
If the length of a chord, drawn at a distance of 21 cm from the centre of a circle, is 40 cm, then the radius (in cm) of the circle is:
P, Q and R can complete a piece of work in 10 days, 15 days and 20 days, respectively.
If they work together, in how many days can they finish the same work?
Ankita sold her watch at 5% loss. If she had sold it for ₹300 more, she would have gained 5%. Find the selling price of the watch.
What is the value of the given expression?
$$\frac{4^{a+4} - 5 \times 4^{a+2}}{15 \times 4^{a} - 2^{2} \times 4^{a}}$$
If $$720 \div 8 + 915 \div 15- m + 32 \times 5 = 1104 \div 16 \times 111 \div 37$$, then the value of m is:
P takes twice as long as Q or three times as long as R to complete a task. If they work together, they can complete the task in two days. How long will it take Q to complete the task on his own?
The length of each side of a triangle is 12 cm. What is the length of the circumradius of the triangle?
Solve the following.
$$22 - \left[9 -\left\{6 - \left(10 - 4 + 3\right)\right\}\right] \div 2 \times 3$$
A policeman chases a thief. The speeds of the policeman and the thief are 8 km/h and 6 km/h, respectively. If the policeman started 10 minutes late, at what distance he will catch the thief?
If $$a = 101, b = 102$$ and $$c = 103$$, then $$a^{2} + b^{2} + c^{2} - ab - be - ca$$ = _________.