In an examination A has scored 20 marks more than B. if B has scored 5% less marks than A , how much has B scored ?
a 360.
b 380.
c 400.
d 420.
pls explain
Answers
Answer:
b) 380
Step-by-step explanation:
Marks scored by A = 20 + B ——(i)
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of A
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we get
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we getMarks scored by A = 20+ 0.95A
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we getMarks scored by A = 20+ 0.95Aor A - 0.95A = 20
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we getMarks scored by A = 20+ 0.95Aor A - 0.95A = 20or 0.05 A = 20
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we getMarks scored by A = 20+ 0.95Aor A - 0.95A = 20or 0.05 A = 20or A = 400
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we getMarks scored by A = 20+ 0.95Aor A - 0.95A = 20or 0.05 A = 20or A = 400Substituting the value of A in (i), we get
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we getMarks scored by A = 20+ 0.95Aor A - 0.95A = 20or 0.05 A = 20or A = 400Substituting the value of A in (i), we get400 = 20 + B
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we getMarks scored by A = 20+ 0.95Aor A - 0.95A = 20or 0.05 A = 20or A = 400Substituting the value of A in (i), we get400 = 20 + Bor B = 400–20
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we getMarks scored by A = 20+ 0.95Aor A - 0.95A = 20or 0.05 A = 20or A = 400Substituting the value of A in (i), we get400 = 20 + Bor B = 400–20or B = 380
Marks scored by A = 20 + B ——(i)Marks scored by B = (100 - 5)% of A.= 95% of Aor marks scored by B = 0.95A ——(ii)Substituting 0.95 A for B in (i), we getMarks scored by A = 20+ 0.95Aor A - 0.95A = 20or 0.05 A = 20or A = 400Substituting the value of A in (i), we get400 = 20 + Bor B = 400–20or B = 380Thus the marks scored by B are 380