Costume + corrections (spare)Wed 30 September1 / 2

All four September costumes　+　corrections

One question from each of the four. There are not many different tools inside them

Name Date

September's four costumes

IT: screen resolution　machines: gears　music: string length　chemistry: balancing

Today there is one question from each of the four. The last question asks which tool each of them used.

1 · All four costumes

1IT — a photo is 4032 by 3024, and their GCD is 1008. Find the ratio.

2Machines — gears of 14 and 21 teeth. After how many teeth do they line up again, and how many turns has each made?

3Music — on a 72 cm string, how long is F (length ³⁄₄)? And G (length ²⁄₃)?

4Chemistry — fill in　□H₂ ＋ □N₂ → □NH₃

5Which tool did each of questions 1 to 4 use? Choose from "greatest common divisor", "lowest common multiple" and "fractions". One of them comes up twice.

This is the important one today.

Costume + corrections (spare)Wed 30 September2 / 2

All four September costumes　+　corrections

Name Date

2 · September's corrections

6From the corrections notebook, pick two you have not yet done a second time, and do them.

Once you can do a question the second time, that unit is finished.

3 · Looking at October

7October starts with dividing decimals. ¹⁄₂ written as a decimal is 0.5. What are ³⁄₄ and ¹⁄₅ as decimals?

Fractions and decimals are two ways of writing the same thing.

8Write 0.6 as a fraction, cancelled down.

9Write ¹⁄₈ as a decimal.

It is 1 ÷ 8.

10Pick the tool you used most in September and write a question of your own that needs it. Write the answer too.