Q82.Let ๐1 = 8, ๐2, ๐3, โฆ . ๐๐ be an A.P. If the sum of its first four terms is 50 and the sum of its last four terms is 170 , then the product of its middle two terms is _____ .
What This Question Tests
This question involves using the properties of arithmetic progression, including sum of terms, to find the common difference and then compute the product of specific terms.
Concepts Tested
Formulas Used
an = a + (n-1)d
Sn = n/2 * (2a + (n-1)d)
๐ NCERT Sections This Tests
8.17 โ Complete Each Synthesis By Giving Missing Starting Material, Reagent Or Products
Chemistry Class 12 ยท Chapter 8
8.17 Complete each synthesis by giving missing starting material, reagent or products
8.2 โ Name The Following Compounds According To Iupac System Of Nomenclature:
Chemistry Class 12 ยท Chapter 8
8.2 Name the following compounds according to IUPAC system of nomenclature: (i) CH3CH(CH3)CH2CH2CHO (ii) CH3CH2COCH(C2H5)CH2CH2Cl (iii) CH3CH=CHCHO (iv) CH3COCH2COCH3 (v) CH3CH(CH3)CH2C(CH3)2COCH3 (vi) (CH3)3CCH2COOH (vii) OHCC6H4CHO-p
2.1 โ Two Charges 5 ร 10โ8 C And โ3 ร 10โ8 C Are Located 16 Cm Apart. At
Physics Class 11 ยท Chapter 2
2.1 Two charges 5 ร 10โ8 C and โ3 ร 10โ8 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.
๐ Question Details
- Chapter
- Sequences & Series
- Topic
- Arithmetic progression (AP)
- Year
- 2023
- Shift
- 01 Feb Shift 1
- Q Number
- Q82
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 9: Sequences and Series
More from this Chapter
Q86.In a geometric progression consisting of positive terms, each term equals the sum of the next two terms. Then the common ratio of this progression equals (1) 1 2 (1 โโ5) (2) 21 โ5 (3) โ5 (4) 12 (โ5 โ1)
Q88.The sum of the series 2! 1 โ13! + 4!1 โโฆ upto infinity is (1) eโ2 (2) eโ1 (3) eโ1/2 (4) e1/2
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Q76.The first two terms of a geometric progression add up to 12. The sum of the third and the fourth terms is 48. If the terms of the geometric progression are alternately positive and negative, then the first term is (1) โ4 (2) โ12 (3) 12 (4) 4