Question 3 - Page 137 - ‘Think of a Number’ Tricks - Chapter 6 Class 8 - Algebra Play (Ganita Prakash II)

Transcript

Question 3 - Page 137 Can you change the steps in this trick and still find the original date? Instead of subtracting 165 from the final answer, you might have to subtract some other number.The 165 only exists because of the specific random numbers Shubham chose to add (the 6 and the 9). If you change those additions, you change the disguise. Let's invent a new sequence where we change the "Add 6" step to "Add 2": Start: M Multiply by 𝟓:𝟓𝐌 Add 2: 5M+2 Multiply by 4: 4∗(5𝑀+2)=20𝑀+8 Add 9: 20M+8+9=20M+17 Multiply by 5: 5 × (20M+17)=100M+85 Add the Day: 100M+85+D In this modified trick, the disguise is now 85. To find the date, you would ask your friend for their final number and subtract 𝟖𝟓 instead of 165 !