Question

please help I'll mark you the brilliantest I promise :(<3
1) find the arithmetic mean of the first five natural numbers
2) a) express 235 praise as rupees using decimals
B) express 8.45km in cm
3) convert 3n +7=1 in statement form

Answer 1

Question-

1) Find the arithmetic mean of the first five natural numbers

2) a) Express 235 praise as rupees using decimals

   b) Express 8.45km in cm

3) Convert 3n +7=1 in statement form

Answer-

1)

The first five natural numbers are : 1,2,3,4,5

MEAN= SUM/Total number

⇒ (1 + 2 + 3 + 4 + 5)/5

⇒ 15/5

⇒ 3

2)

a) ₹ 1 = 100p

  ⇒ 1p = ₹ 1/100

  ⇒ 235p = ₹ 235/100

  ⇒ 235p = ₹ 2.35

b) 1 km = 1000 m

   1 m = 100 cm

   ⇒ 1000 m = 1000 × 100 cm

   ⇒ 1000 m = 100000 cm

   ∴ 1 km = 100000 cm

   ⇒ 8.45 km = 8.45 × 100000 cm

   ⇒ 8.45 km = 845000 cm = 8.45 × 10⁵ cm

3)

3n + 7 = 1 in statement,

1. Seven added to three times a number is one
2. Seven added to thrice a number is one
3. One is the result when seven  is added to thrice a number
4. One is the result when seven is added to three times a number

You can also write,

1. One subtracted from thrice a number results in seven
2. One subtracted from three times a number results in seven

Proof-

From the above two statements, we can write the following equation-

3n - 1 = 7

⇒ 3n + 7 = 1

This is the same thing.