A steamer goes downstream from one point to another in 7
hours. It covers the same distance upstream in 8 hours. If
the speed of stream be 2 km/hr, find the speed of the
steamer in still water and the distance between the ports.
The present age of father is four times the age of his son.
After 10 years, age of father will become three times the
age of his son. Find their present ages.
Fifteen added to thrice a whole number gives 93. The number is __________.
If 3x – 4 (64 – x) = 10, then the value of x is
(a) –266 (b) 133 (c) 66.5 (d) 38
13 and 31 is a strange pair of numbers such that their squares 169
and 961 are also mirror images of each other. Can you find two other
such pairs?
A three digit perfect square is such that if it is viewed upside down,
the number seen is also a perfect square. What is the number?
(Hint: The digits 1, 0 and 8 stay the same when viewed upside down,
whereas 9 becomes 6 and 6 becomes 9.)
The perimeters of two squares are 40 and 96 metres respectively.
Find the perimeter of another square equal in area to the sum of the
first two squares.
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