to find the height of the Great Pyramid in meters, use the clues given...

Question

the clues are...

 

the tenths digit is 4 more than the hundreds digit

the tenths digit is the only prime number in this decimal

the tens digit is 4 times the hundreds digit

the units digit is 1 more than the tenths digit

Answer 1

let the number be abc.d

d=a+4

b=4a

c=d+1

d is the only prime so a has to be 1 because 1+4=5(the only primes greater than 4 are 5, and 7)

if a were 3, then 4a would be 12 which is not a single digit

a=1

d=1+4=5

b=4(1)=4

c=5+1=6

the number is 146.5 m

 

Answer 2

Here's a table for the hundreds place and the tenths place. From the first piece of information we have the following possibilities.

hundred place      tenths place

   1                             5

   2                             6

   3                             7

   4                             8

   5                             9

 

From the second piece of information, ONLY the tenths digit is prime. only the numbers 5 and 7 are prime in the tenths column above.

so   hundred place   tenths place

              1                       5

              3                       7

 

But the second possibility can't happen since BOTH 3 and 7 are prime. 

 

So 1 is in the hundreds place and 5 is in the tenths place. The rest is easy.

The tens place is 4*1 = 4 and the ones place is 5 + 1 =6

 

So the height is 146.5 meters.