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How should I present my working out?

Presenting your working out is extremely important because it's makes the examiners jobs easier, keeping them happy.One thing you should aim to do is not write too small, try and use all the space you're giv...
MS
Answered by Maddie S. • Maths tutor
5333 Views

There are 5 white socks and 3 black socks in a draw. Steven takes out 2 at random. Work out the probability that Steven takes out 2 socks of the same colour.

P(WW) = 5/8 x 4/7 = 20/56 P(BB) = 3/8 x 2/7 = 6/56 P(same colour) = 20/56 + 6/56 = 26/56 = 13/28 (simplified)
TJ
Answered by Tom J. • Maths tutor
8967 Views

ABC is a right angled triangle. D is the point on AB such that AD = 3DB. AC = 2DB and angle A = 90 degrees. Show that sinC = k/√20 where k is an integer. Find the value of k

AB = 4DB AC = 2DB Find BC using Pythagoras: BC = √(4DB) 2 + (2DB) 2 BC = √20DB 2 = √20 DB sinC = opp/hyp = 4DB/√20DB = 4/√20 so k = 4
TJ
Answered by Tom J. • Maths tutor
16467 Views

Solve 7(k – 3) = 3k – 5

Step 1: 7k-21=3k-5 Step 2: 4k=16 Step 3: k=4
JY
Answered by Jin Yang Q. • Maths tutor
7853 Views

Solve the equation 3x squared + 4x – 12 = 0 Give your solutions correct to 2 decimal places.

3x 2 +4x-12=0 Step 1: formula (-b+/- square root (b 2 -4ac))/2a Step 2: a=3 b=4 c=-12 Step 3: type into your calculator Step 4: answer 1.44, or -2.77
JY
Answered by Jin Yang Q. • Maths tutor
17637 Views