Question

If A:B=3:4,B:C=5:7,FIND A:B:C

Answer 1

a:b=3:4
b:c=5:7
we want to equalize b value
take lcm of 4,5
lcm is 20
so
a:b=(3:4)5=15:20
b:c=(5:7)4=20:28
a:b:c=15:20:28

Answer 2

Answer:

$A:B:C= 15:20:28$

Step-by-step explanation:

$Given \: A:B =3:4,\: and \\B:C=5:7$

$We \: know \: that ,\\If\:\frac{A}{B}=\frac{r}{s}; \:and\:\frac{B}{C}=\frac{t}{u},\\then\\A:B:C=(r\times t):(s\times t):(s\times u)$

$Now,\\Here ,\:r=3,\:s=4,\:t=5,\:u=7\\A:B:C=(3\times 5):(4\times 5):(4\times 7)\\=15:20:28$

Therefore,

$A:B:C= 15:20:28$

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