Q71.The number of terms common to the two A.P.’s 3, 7, 11, … , 407 and 2, 9, 16, … , 709 is ____________.
What This Question Tests
This problem requires finding the number of common terms between two arithmetic progressions by identifying the first common term and the common difference of the sequence formed by common terms (which is the LCM of individual common differences).
Concepts Tested
Formulas Used
a_n = a + (n-1)d
LCM of common differences
📚 NCERT Sections This Tests
2.1 — Two Charges 5 × 10–8 C And –3 × 10–8 C Are Located 16 Cm Apart. At
Physics Class 11 · Chapter 2
2.1 Two charges 5 × 10–8 C and –3 × 10–8 C are located 16 cm apart. At what point(s) on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero.
2.2 — A Regular Hexagon Of Side 10 Cm Has A Charge 5 Mc At Each Of Its
Physics Class 11 · Chapter 2
2.2 A regular hexagon of side 10 cm has a charge 5 mC at each of its vertices. Calculate the potential at the centre of the hexagon.
4.7 — Two Long And Parallel Straight Wires A And B Carrying Currents Of
Physics Class 11 · Chapter 4
4.7 Two long and parallel straight wires A and B carrying currents of 8.0 A and 5.0 A in the same direction are separated by a distance of 4.0 cm. Estimate the force on a 10 cm section of wire A.
📋 Question Details
- Chapter
- Sequences & Series
- Topic
- Common terms in two APs
- Year
- 2020
- Shift
- 09 Jan Shift 2
- Q Number
- Q71
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
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