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A rectangle has a perimeter of 50 cm. If the ratio of its length to its width is 3:2, find the length of the rectangle?

Answer 1

Ella Armstrong

Length is #15cm.# and width is #10cm.#

As length and width are in the ratio of #3:2#, let these be #3x# and #2x#

then perimeter is#2xx(3x+2x)=2xx5x=10x#

Hence #10x=50#

or #x=50/10=5cm.#

and length is #3xx5=15cm.# and width is #2xx5=10cm.#

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Answer 2

Caroline Aucoin

Length #l =15cm#

Perimeter #(P) is the total distance around the sides.

Let length#= l # and width #= w #

#P = 2l + 2w# .....(1)

We are told that the ratio of #l# to #w# is #3:2# so

#l/w = 3/2#

#l = 3/2w# .....(2)

Substitute for #l# in (1) #P = 2*(3/2w) + 2w = 5w#

But #P = 50cm# so # 5w = 50cm# #w = 10 cm#

Substitute #w = 10 # into (2) #l = 3/2*10 =15#

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Answer 3

Theodore Abad

#"length "=15" cm"#

#"sum the parts of the ratio "3+2=5#

#P=2(l+b)=50#

#l+b=50/2=25#

#25/5=5larrcolor(blue)"1 part"#

#"length (l)"=5xx3=15" cm"#

#"breadth (b)"=5xx2=10" cm"#

#P=2(15+10)=2xx25=50" cm"#

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.