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Angela 發問於 科學及數學數學 · 1 十年前

# Maths qusetions!! (Hard)

Please Work these following questions out

I am stuck=(

1) A large tub of popcorn costs ￡3.80 and holds 280g.

A regular tub of popcorns costs ￡3.50 and holds 175g.

Rob says that 200g Large tub is the better value for money.

Linda says that 175g Regular tub is the better value for money.

-Who is correct?

-Explain the reasons for your answer.You must show all your working.

2) This item appeared in a newspaper

Cows produce 3% more milk

A farmer found that when his cow listened to classical music the milk it produced increased by 3%.

This increase of 3% represented 0.72 Litres if milk

-Calculate the amount of milk produced by the cow when it litened to classical music.

3) PQR is a right-angled triangle.

PR= 6cm

QR= 4cm

-Work out the length og PQ

-Give your answer in 3 significant figyres.

Thanks very much=D

### 1 個解答

• 1 十年前
最愛解答

Q1:

280g for ￡3.8 so each gram is ￡0.01357

175g for ￡3.5 so each gram is ￡0.02

Therefore the large tub is cheaper (ie 175g for ￡3.5 is more expensive).

Q2:

0.72L is 3% so that total before the increase is 100% = 24L

After the increase, the total will be 24.72L

Q3:

I am assuming angle PQR is the right angle (from your notation). This implies 62 = 42 + (PQ)2

==> 36 = 16 + (PQ)2

==> 20 = (PQ)2

==> PQ = 4.472