If, \( \frac{r}{13} + \frac{13}{r} = 1 \) then the value of r³ is:
If \( \frac{a}{b} + \frac{b}{a} = -1 \) and a - b = 2, then the value of a3 - b3 is:
A person borrowed ₹2,000 at 5% annual simple interest repayable in 3 equal annual installments. What will be the annual installment?
\( \text{₹}730 \tfrac{10}{63} \)
\( \text{₹}840 \tfrac{9}{61} \)
\( \text{₹}640 \tfrac{11}{63} \)
\( \text{₹}250 \tfrac{10}{63} \)
Two persons A and B working separately can sanitise a building in 6 and 10 hours, respectively. They work in stretches of one hour alternately. If A begins at 8 a.m., then when will the work be finished?
\( 9 \tfrac{1}{3} \text{ h} \)
\( 7 \tfrac{1}{3} \text{ h} \)
\( 6 \tfrac{1}{3} \text{ h} \)
\( 8 \tfrac{1}{3} \text{ h} \)
The area of two similar triangles are 324 cm² and 289 cm², respectively. What is the ratio of their corresponding altitudes?
\( \frac{17}{18} \)
\( \frac{17}{19} \)
\( \frac{19}{17} \)
\( \frac{18}{17} \)
The pie-chart shows marks of a student in different subjects out of 100. 
The marks scored in Hindi and Mathematics are more than the marks scored in English and Science by:
If ∆ABC ≅ ∆PQR and ∠ABC = (x + 60)°, ∠PQR = (85 - 4x)°, and ∠RPQ = (3x + 65)°, then the value of ∠ABC in degree is: