# Series/Addition/Subtraction
Q1 Find 8 + 888 + 8888 + 88888 ?a) 97760 b) 98572 c) 98672 d) 97672 e) None of the above
Q2. Find 9.4 + 99.44 + 999.444 + 9999.4444 ?
a) 11207.728 b) 11107.728 c) 11106.728 d) 11111.728 e) None of these
a) 48.104 b) 47.104 c) 47.204 d) 48.204 e) None of these
Q4. (3-2) [(3)4+((3)3✘2)+(3)2✘(2)2+(3✘23)+24] = ?
a) 311 b) 211 c) 201 c) 221 d) 301 e) None of these
Q5. (125.824+124.654)2 + (125.824-124.54)2 / ((125.824)2+(124.54)2)
a) 1.166 b) 1 b) 2 c) 625 d) 250.478 e) None of these
Q6. Evaluate 1 + 1/1*3 + 1/1*3*9 + 1/1*3*9*27 + 1/1*3*9*27*81 up to three places of decimals ?
a)1.367 b) 1.370 c) 1.361 d) 1.267 e) None of these
Q7. 2 ÷ [2+ 2÷{2+2 ÷ 4)}]= x / 19. Find x.
a) 3 b) 4 c) 5 d) 6 e) None of these
a) 0.67 b) 0.77 c) 0.87 d) 0.97 e) None of these
Q9) Find the sum of all even natural numbers less than 75.
a) 1416 b) 1426 c) 1396 d) 1406 e) None of these
Solution:
(1)Sol : Option (c)
8*(12345) - 88 = 98672
(2)
Sol: Option (b)
9✘(1234) = 11106
4✘(4321) = 17284
=1.7284
=11106+1.7284=11107.7284
(3)
Sol: Option (a)
(a3 + b3)=(a+b) (a2-ab+b2)
a = 2.3, b = 3.3;
(a)3 = 12.167, (b)3 = 35.937 (a3+b3)=48.104
(4)
Sol: option (b)
(a5-b5)=(a-b) [a4+a3b+a2b2+ab3+b4] = ?
a = 3, b = 2; (3)5=243, (2)5 =32;
(a5-b5) = 243-32= 211
Sol: Option (b)
9✘(1234) = 11106
4✘(4321) = 17284
=1.7284
=11106+1.7284=11107.7284
(3)
Sol: Option (a)
(a3 + b3)=(a+b) (a2-ab+b2)
a = 2.3, b = 3.3;
(a)3 = 12.167, (b)3 = 35.937 (a3+b3)=48.104
(4)
Sol: option (b)
(a5-b5)=(a-b) [a4+a3b+a2b2+ab3+b4] = ?
a = 3, b = 2; (3)5=243, (2)5 =32;
(a5-b5) = 243-32= 211
(5)
Sol: Option (b)
(a+b)2 + (a-b)2=2((a)2+(b)2) Hence Answer is 2
(6)
Sol: Option (a)
1+0.33+0.0370 ... hence (a) is the answer no further addition is required.
(7)
Sol: option (e)
Using VODMAS method
Step 1. [ 2+ 2/4 ] = 5/2.
Step 2. ( 2 + 2 ÷5/2) = 2÷ 2✘2/5 =14/5
Step 3. [2+2÷14/5]=2+2*5/14=19/7
Step 4. L.H.S = 2÷19/7=14/19 = x/19 Hence x=19
(8)
Sol: Option (c)
= -4 + 0.45 + 2 + <sup>927-9</sup>/<sub>990</sub> +6/9
= -4 + 0.45 + 2 + <sup>918</sup>/990 +3/2
= (- 4 + 2) + (0.45+1.5) + (<sup>51</sup>/55)
= -2 + 1.95 + 0.92 = 0.87
(9)
Sol: Option (d)
sum= 2 + 4 + 6 + ...+74 a=2 , d=(4-2)=2,l=74 n=37; sum= n/2 (a+l) 37/2✘(2+74)=(37✘38) =37✘(40-2) =(37✘40)-(37✘2) =(1480-74)=1406
Download Simplification notes in PDF