Question

without using a measuring scale how can you find the area of the following correctly ?
(a)5 rupees coin
(b)A playing card
(c)A banayan leaf

​

Answer 1

The answer is playing cards ok when we have no measuring scale but we can use our own hands also because it is only for square as u ask measuring scale

Answer 2

${\fbox{\boxed {\huge{\rm{\red{Answer}}}}}}$

Explanation:

To estimate the area of an irregular object (a lamina) or object whose radius or length of side is not known, a graph paper is to be used.  A graph paper is a sheet of paper on which horizontal and vertical lines are ruled at a regular interval of 1 mm.  After each 1 cm space the line is made thick such that area of one small square formed becomes 1 mm × 1 mm = 1 mm2 and that of the big square becomes 1 cm × 1 cm = 1 cm2.  Place the object 2D object on the graph paper and draw its boundary (outline) with a pencil.  After this, count the number of complete squares and the squares more than half within the boundary.  Area of the surface = the sum of the squares mentioned above.   For example,  Let's see how to find area of playing card,   

⬆⬆⬆⬆Attechment⬆⬆⬆⬆

Here, you can see the outline of the playing card marked on the graph paper. The small dots on graph represents full squares under the outline of playing card  and the circles on the extreme right represents half squares coming under the outline.

If you count you will get following count. 

Full squares = 54 

half squares = 6   

${\rm{Area \: of \: the \: playing \: card }}$

${\rm{ =54 (full \: square) + 6 (half \: square)}} {\rm{ = 54 + 3 = 57square}}$${\rm{hence}}$

${\rm{Area \: of \: the \: playing = 57}} {cm}^{2}$ ${\rm{\therefore \: 1square = 1 {cm}^{2}}}$

Thus, calculation of area of playing card will be as follows: -  Similarly you can try this for coin and leaf.   

${\huge{\green{\rm{bebrainly}}}}$