Last monts, kiera ran 22 more miles than Bianca did. If they ran a combined total of 86 miles, how many miles did bianca run ?

Options

A. 27
B. 37
C. 43
D. 54

Answer

B

Explanation

The question gives two unknowns and enouth information to create a system of equations, therefore, it could be solved with a traditional algebraic approach.
There is , however, a more efficient way: assess the answer choices to see which makes sense for Bianca's distnace. Since Kiera ran 22 miles farther than Bianca, and the combined distance they ran is 86 miles, Bianca must have run less than half of 86 milies. Since one-half of 86 is 43, you can quickly eliminate (C ) and (D), which are both too big.
Now check (B) against the known information. If Bianca ran 32 miles, then Kiera ran `32 +22 =54` miles. Check if Bianca's distance and Kiera's distance add up to `86:32+54=86,` thus, (B) is correct.
If you're curious about the algebraic approach., here It is:let b stand for the number f miles Bianca ran and k stand for the number of miles kiera ran. Then `b +k =86, and k =b+ 22.` Now, substitute the value of k in terms of b into the first equation:
`b + (b +22 ) =86`
` 2b + 22= 86`
`2b =64`
`b =32`
Again, Bianca ran 32 miles, and (B) is correct.