Home › ICSE Class 10 › mathematics › Arithmetic Progression › If 4th term is 11 and 9th term is 26, first term…
If 4th term is 11 and 9th term is 26, first term is
A2
B5
C3
D1
Answer & Solution
Correct answer: A. 2
1. a + 3 d = 11 and a + 8 d = 26.
2. Subtract: 5 d = 15, so d = 3.
3. Substitute back: a + 9 = 11, so a = 2.
4. Hence the first term is 2.
_Source: Selina Concise Mathematics Class 10, Ch on Arithmetic Progression (Mistral OCR'd PDF), section on simultaneous equations_
Related questions
Rupees 720 was divided among A, B, C, D and E. The amounts received were in ascending ordeIf S_n = n^2 + 3 n, then first term and common difference areHow many three-digit numbers are divisible by 6?If sum of an AP is 100 and a = 5, l = 15, number of terms isIf a_n = 3 n + 5, the first three terms areSum of all natural numbers between 100 and 200 divisible by 7 isMiddle term of the AP 1, 5, 9, ..., 49 isSum of an AP with first term 7, last term 47 and 9 terms is