Rates and variations questions | form three Basic Mathematics

If q∗r =q - 4r, find x given that 3∗(1∗x) = 27.

Answer / Solution

Given 3∗(1∗x) = 27. but
q∗r =q - 4r,
q_i∗r_i =q_i - 4r_i,
Let 3=q₁, and (1∗x)=r₁
also
Let 1=q₂, and (x)=r₂
starting from inside: by applying q∗r =q - 4r,
3 ∗(1 - 4x)=27 then
3 - 4(1 - 4x) = 27.
3 - 4 + 16x = 27
-1 + 16x = 27 ⇒ 16x = 28
^16x/₁₆ = _{28/16
∴ From 3∗(1∗x) = 27 the value of x = ⁷/4.}

If , evaluate .

Answer / Solution

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Answer / Solution

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Answer / Solution

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Answer / Solution

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