If S = (4t + 3)(t - 2), find ds/dt when t = 5 secs.
50 units per sec
35 units per sec
22 units per sec
13 units per sec
Correct answer is B
\(s = (4t + 3)(t - 2)\)
\(\frac{\mathrm d s}{\mathrm d t} = (4t + 3)(1) + (t - 2)(4)\)
= \(4t + 3 + 4t - 8\)
= 8t - 5
\(\frac{\mathrm d s}{\mathrm d t} (t = 5 secs) = 8(5) - 5\)
= 40 - 5
= 35 units per sec
Find the value of \(\frac{(0.5436)^3}{0.017 \times 0.219}\) to 3 significant figures.
46.2
43.1
534
431
Correct answer is B
(\frac{(0.5436)^3}{0.017 \times 0.219}\)
= \(\frac{0.16063}{0.017 \times 0.219}\)
= 43.1 (to 3 s.f)
Simplify 81\(^{\frac{-3}{4}}\) x 25\(^{\frac{1}{2}}\) x 243\(^{\frac{2}{5}}\)
\(\frac{2}{5}\)
\(\frac{3}{5}\)
\(\frac{5}{2}\)
\(\frac{5}{3}\)
Correct answer is D
81\(^{\frac{-3}{4}}\) x 25\(^{\frac{1}{2}}\) x 243\(^{\frac{2}{5}}\)
= \((\sqrt[4]{81})^{-3} \times \sqrt{25} \times (\sqrt[5]{243})^2\)
= \(\frac{5 \times 3^2}{3^{3}}\)
= \(\frac{5}{3}\)
19%
20%
25%
16.3%
Correct answer is A
S.I = \(\frac{PRT}{100}\)
\(\implies\) N 4890 = \(\frac{8550 \times 3 \times x}{100}\)
\(x = \frac{4890 \times 100}{8550 \times 3}\)
\(x = 19.06%\)
\(x \approxeq 19%\)
43.6% loss
35% profit
63.2% profit
28% loss
Correct answer is C
200 mangoes at 4 for N2.50
\(\implies\) Total cost price = \(\frac{200}{4} \times N 2.50\)
= N 125.00
Since 30 mangoes got spoilt \(\implies\) Left over = 200 - 30
= 170 mangoes
170 mangoes at 2 for N 2.40
\(\implies\) Total selling point = \(\frac{170}{2} \times N 2.40\)
= N 204.00
Profit : N (204.00 - 125.00) = N 79.00
% profit = \(\frac{79}{125} \times 100%\)
= 63.2% profit.