## Wednesday, September 14, 2011

### Maths Questions (4m)

1. Mr Yeo bought 4 times as many spoons as bowls and spent \$495 in total.
He spent \$15 more on the bowls than on the spoons.
If a bowl cost \$6.50 more than a spoon, what was the cost of a spoon ?

2. A car took 5 hours to travel from Town A to Town B while a bus took
4 hours longer to travel from Town B to Town A.
Both vehicles set off at the same time and moved towards each other.
Two hours later, they were 255 km apart. What was the speed of the bus ?

1. I have two questions that I do not know so I hoped that you will help me.

Question 1: 1/4x5 + 1/5x6 + 1/6x7 +... + 1/48x49 + 1/49x50 =_______________

What is the missing number in the blank?

Question 2: Mrs Jones earned 15 percent from the sale of a diamond ring and 20 percent from the sale of a diamond bracelet. Her total earnings for both items was \$195. She also sold a similar bracelet at a discount of 10 percent off the selling price of the first bracelet. The total amount earned for the three items was \$243. Find the cost price of the ring.

2. Guys help me with this question:

Matthew, Joanne and Paul ran in a race. When Matthew reached the finishing line in 10 minutes, Joanne had only run 5/8 of the distance. Her average running speed is 7.5m/min slower than Matthew's speed. When she completed the race, Paul was still 72m behind her.

a) What was Matthew's average running speed in km/h?

b) What was Paul's average running speed in m/min?

3. @My name is Keane

1) 0.9km/hr
b)3.9m/min?

Take Matthew's speed as u. Joanne is u-7.5. Distance travelled by Matthew is 10u. By Joanne is 7.5u-75m

The difference of 75m travelled by them is also equal 3p of the whole distance (as Joanne travelled 5/8th)

So 3p=75m
p=15m.

Total distance is 10p = 150m.
Mathew's speed is - 15m/min which is 0.9km/hr

b) Joanne's speed is 7.5m/min. She took 20 mins to complete the race. In 20 min - Paul ran 150m-72m = 78m.

So his speed is 78m/20min =3.9m/min.

Makes sense?

4. @Augustine

2)Lets say cost price of Bracelet is 100%b and of ring is 100%r. Sale price of first bracelet is 120%b. Sale price of 2nd bracelet is 90% of 120%b =108%b.

We know earning(=profit =sale price-costprice) from 2nd diamond bracelet is \$48 (\$243-\$195).

If sale price is 108%b and cost price is 100%b - then profit is 8%. 8% = \$48
100% = \$600.
Cost price of bracelet is \$600.
Sale price = 120% of \$600 = \$720
So earning from bracelet =\$120.

We know earnings from bracelet + ring is =\$195.

So earnings from ring alone = \$75

We also know ring was sold at 115% - therefore earning in % is 15%

15% = \$75
100% = \$500

Cost price of ring was \$500.

5. @MY name is Keane

Erata : " Distance travelled by Matthew is 10u. By Joanne is 7.5u-75m"