If x + 0.4y = 3 and y = \(\frac{1}{2}\)x, find the value of (x + y)
1\(\frac{1}{4}\)
2\(\frac{1}{2}\)
3\(\frac{3}{4}\)
5
Correct answer is C
x + 0.4y = 3...(i)
y = \(\frac{1}{2}\)x
x = 2y
x - 2y = 0....(ii)
solve simultaneously; x + 0.4y
= 3 - x - 2y = 0
2.4 = 3
y = \(\frac{3 \times 10}{2.4 \times 10} \)
= \(\frac{30}{24} = \frac{5}{4}\)
x - 2(\(\frac{5}{4}\)) = 0
x - \(\frac{5}{2}\) = 0
x = \(\frac{5}{2}\)
x + y = \(\frac{5}{2} + \frac{5}{4}\)
\(\frac{10 + 5}{4} = \frac{15}{4}\)
= 3\(\frac{3}{4}\)
Which of these statements about y = 8\(\sqrt{m}\) is correct?
log y = log 8 x log \(\sqrt{m}\)
log y = 3 log 2 x \(\frac{1}{2}\) log m
log y = 3 log 2 - \(\frac{1}{2}\) log m
log y = 3 log 2 + \(\frac{1}{2}\) log m
Correct answer is D
y = 8\(\sqrt{m}\); log y = log 8\(\sqrt{m}\)
log y = log 8 + log \(\sqrt{m}\)
log y = log 23 + log m\(\frac{1}{2}\)
log y = 3 log 3 + \(\frac{1}{2}\) log m
\(\frac{8}{15}\)
\(\frac{13}{25}\)
\(\frac{11}{15}\)
\(\frac{13}{15}\)
Correct answer is A
Prob(RB + BR) = Total balls = 4 + 6 = 10
= prob(\(\frac{4}{10} \times \frac{6}{9}\)) + prob(\(\frac{6}{10} \times \frac{4}{9}) = \frac{24}{90} + \frac{24}{90}\)
= \(\frac{48}{90} = \frac{16}{30} = \frac{8}{15}\)
\(\sqrt{10}\)
4
5
\(\sqrt{30}\)
Correct answer is C
\(\begin{array}{c|c} x & x - x & (x - \bar{x})^2\\ \hline 15 & -6 & 36\\21 & 0 & 0\\17 & -4 & 16\\ 26 & 5 & 25 \\ 18 & -3 &9 \\ 29 & 8 & 64 \end{array}\)
\(E(x - \bar{x})^2\) = 150
N = 6
S.D = \(\sqrt{\frac{(x - x)^2}{N}}\)
S.D = \(\sqrt{\frac{150}{6}}\) = 5
50 tan 30o
50 sin 54o
50 tan 54o
50 sin 36o
Correct answer is B
No explanation has been provided for this answer.