Question

14)
three numbers are in the ratio 3:5:7 and the average is 30. find the smallest number?​

Answer 1

Answer:

let the no. be 3x , 5x , 7x

average = sum of no./3

30 = 3x+5x+7x/3

90 = 15x

x = 6

smallest no. = 3x = 3×6 = 18

Step-by-step explanation:

hope it may help u pls pls pls follow me & mark brainliest ^_^

Answer 2

Answer:

$\large{ \underline{\frak{\pmb{Given...}}}}$

• ➠ Three numbers are in the ratio 3:5:7.
• ➠ The average of number is 30.

$\large \underline\frak{ \pmb{To \: Find...}}$

• ➠ The smallest number

$\large\underline\frak{ \pmb{Formula \: Used...}}$

$\bigstar\underline{\boxed{\sf {\purple{Average =\dfrac{Sum \: of \: Terms }{Number \: of \: Terms }}}}}$

$\large\underline\frak{\pmb{Solution...}}$

$\odot \: \bf \red{Let,The \: Numbers...}$

• $\dashrightarrow \sf{3x}$
• $\dashrightarrow\sf{5x}$
• $\dashrightarrow \sf{7x}$

$\odot \: \bf \red{According \: To \: The \: Question... }$

${:\implies\sf{Average =\dfrac{Sum \: of \: Terms }{Number \: of \: Terms }}}$

• Substituting the numbers

${:\implies\sf{30 =\dfrac{3x+ 5x + 7x}{3}}}$

${:\implies\sf{30 =\dfrac{15x}{3}}}$

${:\implies\sf{30 \times 3 ={15x}}}$

${:\implies\sf{90 ={15x}}}$

${:\implies\sf{x = \dfrac{90}{15} }}$

${:\implies\sf{x = \cancel\dfrac{90}{15} }}$

${:\implies\sf{x = 6}}$

$\bigstar\underline{\boxed{\sf \purple{x = 6}}}$

$\odot \: \bf \red{Numbers... }$

• $\dashrightarrow \sf{3 \times 6 = 18}$
• $\dashrightarrow\sf{5 \times 6 = 30}$
• $\dashrightarrow \sf{7 \times 6 = 42}$

$\large\underline\frak{\pmb{Verification...}}$

${:\implies\sf{Average =\dfrac{Sum \: of \: Terms }{Number \: of \: Terms }}}$

• Substituting the numbers

${:\implies\sf{30 =\dfrac{18+ 30 + 42}{3}}}$

${:\implies\sf{30 =\dfrac{90}{3}}}$

${:\implies\sf{30 = \cancel\dfrac{90}{3}}}$

${:\implies\sf{30 =30}}$

$\bigstar\underline{\boxed{\sf \purple{LHS=RHS }}}$

${\sf\underline{Hence \: Verified }} \: \small\boxed{ \checkmark}$

• ➠ Henceforth,The smallest number is 18..