Question

II. ANSWER ALL THE QUESTIONS
6) Solve: 2x-3 = 15
7) Find the mean of 5,10,15,20,25
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Answer 1

Required Answer :-

• The required number is 9.
• The mean of the numbers are 15.

Step-by-step explanation:

Given Questions:

• Solve: 2x - 3 = 15
• Find the mean of 5, 10, 15, 20, 15

Solution:

• Solve: 2x - 3 = 15

$\sf{\implies \: 2x - 3 = 15} \\ \\ \sf{\implies \: 2x = 15 + 3} \\ \\ \sf{\implies \: 2x = 18} \\ \\ \sf{\implies \: x = \dfrac{18}{2}} \\ \\ \sf{\implies \: x = \cancel{\dfrac{18}{2}}} \\ \\ \bf{\implies \: \boxed{\red{ \bf{x = 9}}}}$

Hence, The required number is 9.

_________________________

• Find the mean of 5, 10, 15, 20 and 25

$\underline{\sf{\large{As \: we \: know \: that,}}}$

$\boxed{\sf{Mean(m) = \dfrac{sum \: of \: numbers}{Number \: of \: numbers}}}$

Therefore,

$\sf{ \longrightarrow \: \dfrac{sum \: of \: numbers}{Number \: of \: numbers}} \\ \\ \sf{ \longrightarrow \: \dfrac{5 + 10 + 15 + 20 + 25}{Number \: of \: numbers}} \\ \\ \sf{ \longrightarrow \: \dfrac{5 + 10 + 15 + 20 + 25}{5}} \\ \\ \sf{ \longrightarrow \: \dfrac{15 + 15 + 20 + 25}{5}} \\ \\ \sf{ \longrightarrow \: \dfrac{30 + 20 + 25}{5}} \\ \\ \sf{ \longrightarrow \: \dfrac{50 + 25}{5}} \\ \\ \sf{ \longrightarrow \: \dfrac{75}{5}} \\ \\ \sf{ \longrightarrow \: \cancel{\dfrac{75}{5}}} \\ \\ \sf{ \longrightarrow \: \boxed{ \bf{ \red{mean = 15}}}}$

Hence, The mean is 15.