"hello students i am data your mass
leader tutor and the today's question is
the amount of
extension in an elastic string varies
directly
with the weight hung on it if a weight
of 250 gram produces an extension of 3.5
centimeter
find the extension produced by the
weight of 700 gram
so in this question we make a table
between the
weight and the extension
extension which is in centimeter
and weight
which is in graph
if extension is 3.5 then weight is 250
if weight is 700 we have to find the
extension but in question it is said
that it varies directly so it's a case
of direct variation
so it's a case of direct variation and
in direct variation
k is equal to x by y
so 3.5 divided by
250 is equal to x
divided by 700 so the value of
x is equal to 700
into 3.5 we cross multiply here
we cross multiply it and
250 and 250 is divided by
so 0 0 cancel
and if we remove this point remove this
point we got ten
so this zero cancel out this zero now
twenty five
fives are sorry five fives are twenty
five five sevens are
now it becomes 49 by five
seven sevenths of 49 divided by 5 and 49
is divided by
5 we got 9.8
grams so this is our answer i hope you
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your questions thank you
"