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#164 Sum thing wrong

Amira presented her homework to her teacher:

2 7 9 7

+ 2 3 6 7

= 4 6 5 4

Wrong, Amira, please check your working.

“I promise you it is right. It is just that I have used a code. Every digit used represents a different digit, and the same digit is always represented by the same ‘wrong’ digit. For example, maybe I replaced all the 6s with 4s. Or maybe I did something else…

“You are giving me a headache, Amira”.

What is the correct sum?

Solution next week

Quick quiz #148

1 A molecule that is neutral overall but has both positively and negatively charged functional groups is known as a what?

2 In what year did NASA’s New Horizons probe fly by Pluto?

3 Cholecalciferol and ergocalciferol are compounds in which vitamin group?

4 What name is given to the horn-like structures on the heads of giraffes and male okapi?

5 Which 20th-century British physicist attended the same primary school as Archibald Leach (later known as actor Cary Grant)?

Answers below

#163 Down for the count

Solution

The contestants managed to get the answers 1, 2, 5 and 9. Here are possible routes to those numbers.

(((100,000 + 10,000) ÷ 1000) – 100) ÷ 10 = 1

((100,000 ÷ 10,000) + (1000 ÷ 100)) ÷ 10 = 2

10,000 ÷ (10 × ((100,000 ÷ 1000) + 100)) = 5

10 – (100,000 × 100) ÷ (10,000 × 1000) = 9