How can we get the numbers (a) 5072, (b) 8300 using as few button clicks as possible? Class 7
hardHow can we get the numbers (a) 5072, (b) 8300 using as few button clicks as possible? Class 7
Question 1.
How can we get the numbers (a) 5072, (b) 8300 using as few button clicks as possible? Class 7
Find out which buttons should be clicked and how many times to get the desired numbers given in the table.
The aim is to click as few buttons as possible.
Here is one way to get the number 5072. This method uses 23 button clicks in total.
Is there another way to get 5072 using less than 23 button clicks?
Write the expression for the same.
Solution:
(a) 5072 = (5 × 1000) + (7 × 10) +(2 × 1) → 14 buttons
(b) 8300 = (8 × 1000) + (3 × 100) → 11 buttons
Question 2.
For the numbers in the previous exercise, find out how to get each number by making the smallest number of button clicks and write the expression. Class 7
Solution:
(a) 8300 = (8 × 1000) + 3 × 100) → 11 buttons
(b) 40629 = (4 × 10000) + (6 × 100) + (2 × 10) + (9 × 1) → 21 buttons
(c) 56354 = 5 × (10000) + (6 × 1000) + 3 × (100) + (5 × 10) + (4 × 1) → 23 buttons
(d) 66666 = (6 × 10000) + (6 × 1000) + (6 × 100) + (6 × 10) + (6 ×. 1) → 30 buttons
(e) 367813 = (3 × 100000) + (6 × 10000) + 7 × (1000) + (8 × 100) + (1 × 10) + (3 × 1) → 28 buttons
Question 3.
Do you see any connection between each number and the corresponding smallest number of button clicks? Class 7
Solution:
Yes. Smallest number of button clicks is equal to sum of the digits of the corresponding number.
Question 4.
If you notice, the expressions for the least button clicks also give the Indian place value notation of the numbers. Think about why this is so. Class 7
Solution:
(a) 8300 = 8,300
(b) 40629 = 40,629
(c) 56354 = 56,354
(d) 66666 = 66,666
(e) 367813 = 3,67,813
As already stated, smallest number of button clicks, in each case, is equal to sum of the digits of the number.