Answer:
[tex]4[/tex] inches.
Step-by-step explanation:
Length of first ribbon [tex]=12[/tex] inches.
Length of second ribbon [tex]=20[/tex] inches.
To find the greatest length he can make of smaller strips that are all equal in length, we need to find the H.C.F of the two numbers.
[tex]12=2\times 2\times 3[/tex]
[tex]20=2\times 2\times 5[/tex]
For H.C.F, we will take the product of all the common factors in the prime factorization of the two numbers.
H.C.F [tex]=2\times 2=4[/tex]
So, he can cut three [tex]4[/tex] inches ribbons from the [tex]12[/tex] inches ribbon and five [tex]4[/tex] inches ribbons from the [tex]20[/tex] inches ribbon.
Hence, the greatest length he can make of smaller strips that are all equal in length is [tex]4[/tex] inches.