Factors And Powers

Question 1

How do you find the highest common factor (HCF) of 2 numbers?

Answer 1

1. Draw the prime trees for both numbers.
2. Draw a venn diagram with one side for prime factors of the 1st number, the other for the 2nd and the middle for prime factors of both.
3. Multiply the middle numbers together.

Question 2

How do you find the lowest common multiple (LCM) of something?

Answer 2

1. Draw the prime trees
2. Draw a venn diagram like with HCF
3. Multiply all the numbers in the venn diagram together

Question 3

When you multiply indices, what do you do to the indices?

Answer 3

Add them together

Question 4

Write 10 to the power of 3 × 10 to the power of 5 as a single power of 10.

Answer 4

10 to the power of 8

Question 5

When you ÷ indices, what do you do to the indices?

Answer 5

Minus them.

Question 6

Write 2 to the power of 9 ÷ 2 to the power of 6 as a single power of 2.

Answer 6

2 to the power of 3

Question 7

When there are brackets involved in indices, what do you do to the indices?

Answer 7

Multiply them.

Question 8

Write (5 to the power of 4) squared as a single power of 5.

Answer 8

5 to the power of 8

Question 9

What is anything to the power of 0?

Answer 9

1

Question 10

What is 3.6245 rounded to 3 significant figures?

Answer 10

3.62

Question 11

What is 0.000456 rounded to 2 significant figures?

Answer 11

0.00046

Question 12

What is 0.0405 rounded to 2 significant figures?

Answer 12

0.041